Training 'convnext_tiny' on multiple GPUs gives this error

I am trying to train ‘convnext_tiny’ on my 16GPUs AWS instance

learn = vision_learner(dls, 'convnext_tiny', pretrained= True, metrics = accuracy, cbs = [SaveModelCallback, CSVLogger(fname='convnext_tiny_stage1.csv')])

print('learner loaded')

with learn.distrib_ctx(sync_bn=False):
    learn.fit_one_cycle(20, 0.00251, cbs=EarlyStoppingCallback(monitor='accuracy'))
    learn.save('convnext_tiny_stage1')

and I am receiving this error:

RuntimeError: Expected to have finished reduction in the prior iteration before starting a new one. This error indicates that your module has parameters that were not used in producing loss. You can enable unused parameter detection by passing the keyword argument `find_unused_parameters=True` to `torch.nn.parallel.DistributedDataParallel`, and by 
making sure all `forward` function outputs participate in calculating loss. 
If you already have done the above, then the distributed data parallel module wasn't able to locate the output tensors in the return value of your module's `forward` function. Please include the loss function and the structure of the return value of `forward` of your module when reporting this issue (e.g. list, dict, iterable).
Parameter indices which did not receive grad for rank 8: 44 45
 In addition, you can set the environment variable TORCH_DISTRIBUTED_DEBUG to either INFO or DETAIL to print out information about which particular parameters did not receive gradient on this rank as part of this error

The complete log:

epoch     train_loss  valid_loss  accuracy  time    
Traceback (most recent call last):--------------------------------------------------------------------------------| 0.01% [1/14439 00:11<47:49:00]
  File "convnext_tiny_stage1.py", line 44, in <module>
    learn.fit_one_cycle(20, 0.00251, cbs=EarlyStoppingCallback(monitor='accuracy'))
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/callback/schedule.py", line 116, in fit_one_cycle
    self.fit(n_epoch, cbs=ParamScheduler(scheds)+L(cbs), reset_opt=reset_opt, wd=wd)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 222, in fit
    self._with_events(self._do_fit, 'fit', CancelFitException, self._end_cleanup)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 164, in _with_events
    try: self(f'before_{event_type}');  f()
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 213, in _do_fit
    self._with_events(self._do_epoch, 'epoch', CancelEpochException)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 164, in _with_events
    try: self(f'before_{event_type}');  f()
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 207, in _do_epoch
    self._do_epoch_train()
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 199, in _do_epoch_train
    self._with_events(self.all_batches, 'train', CancelTrainException)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 164, in _with_events
    try: self(f'before_{event_type}');  f()
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 170, in all_batches
    for o in enumerate(self.dl): self.one_batch(*o)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 195, in one_batch
    self._with_events(self._do_one_batch, 'batch', CancelBatchException)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 164, in _with_events
    try: self(f'before_{event_type}');  f()
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 173, in _do_one_batch
    self.pred = self.model(*self.xb)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib64/python3.7/site-packages/torch/nn/modules/module.py", line 1102, in _call_impl
    return forward_call(*input, **kwargs)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib64/python3.7/site-packages/torch/nn/parallel/distributed.py", line 873, in forward
Traceback (most recent call last):
  File "convnext_tiny_stage1.py", line 44, in <module>
    learn.fit_one_cycle(20, 0.00251, cbs=EarlyStoppingCallback(monitor='accuracy'))
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/callback/schedule.py", line 116, in fit_one_cycle
    self.fit(n_epoch, cbs=ParamScheduler(scheds)+L(cbs), reset_opt=reset_opt, wd=wd)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 222, in fit
    self._with_events(self._do_fit, 'fit', CancelFitException, self._end_cleanup)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 164, in _with_events
    try: self(f'before_{event_type}');  f()
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 213, in _do_fit
    self._with_events(self._do_epoch, 'epoch', CancelEpochException)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 164, in _with_events
    try: self(f'before_{event_type}');  f()
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 207, in _do_epoch
    self._do_epoch_train()
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 199, in _do_epoch_train
    self._with_events(self.all_batches, 'train', CancelTrainException)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 164, in _with_events
    try: self(f'before_{event_type}');  f()
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 170, in all_batches
    for o in enumerate(self.dl): self.one_batch(*o)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 195, in one_batch
    self._with_events(self._do_one_batch, 'batch', CancelBatchException)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 164, in _with_events
    try: self(f'before_{event_type}');  f()
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib/python3.7/site-packages/fastai/learner.py", line 173, in _do_one_batch
    self.pred = self.model(*self.xb)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib64/python3.7/site-packages/torch/nn/modules/module.py", line 1102, in _call_impl
    return forward_call(*input, **kwargs)
  File "/home/aayush/.local/share/virtualenvs/aayush-bykuu7TH/lib64/python3.7/site-packages/torch/nn/parallel/distributed.py", line 873, in forward
    if torch.is_grad_enabled() and self.reducer._rebuild_buckets():
RuntimeError: Expected to have finished reduction in the prior iteration before starting a new one. This error indicates that your module has parameters that were not used in producing loss. You can enable unused parameter detection by passing the keyword argument `find_unused_parameters=True` to `torch.nn.parallel.DistributedDataParallel`, and by 
making sure all `forward` function outputs participate in calculating loss. 
If you already have done the above, then the distributed data parallel module wasn't able to locate the output tensors in the return value of your module's `forward` function. Please include the loss function and the structure of the return value of `forward` of your module when reporting this issue (e.g. list, dict, iterable).
Parameter indices which did not receive grad for rank 1: 44 45
 In addition, you can set the environment variable TORCH_DISTRIBUTED_DEBUG to either INFO or DETAIL to print out information about which particular parameters did not receive gradient on this rank as part of this error

My Environment settings:
timm==0.5.4
fastai==2.6.3
torch==1.10.2
torchvision==0.11.3