Conda env update error on Paperspace

The problem I have after update is the following :
It seems that I can Update butI have activation problem and for now I have no fastai on my Notebook on Paperspace.

I get the error:

to activate this envirounment use:
source activate fastai

and when I tray to run this command I get the following error:

source: not found

after some searches I tried :

conda activate fastai

I also get error:

CommandNotFoundError: Your shell has not been properly configured to use 'conda activate'.
If your shell is Bash or a Bourne variant, enable conda for the current user with

$ echo ". /opt/conda/etc/profile.d/conda.sh" >> ~/.bashrc

or, for all users, enable conda with

$ sudo ln -s /opt/conda/etc/profile.d/conda.sh /etc/profile.d/conda.sh

The options above will permanently enable the 'conda' command, but they do NOT
put conda's base (root) environment on PATH. To do so, run

$ conda activate

in your terminal, or to put the base environment on PATH permanently, run

$ echo "conda activate" >> ~/.bashrc

Previous to conda 4.4, the recommended way to activate conda was to modify PATH in
your ~/.bashrc file. You should manually remove the line that looks like

export PATH="/opt/conda/bin:$PATH"

after trying all the above mentioned command I still cget the same error as above after running the command.

I also tried:

activate conda

and it also give me the error:

/bin/sh: 8: activate: Permission denied

P.S. I use Paperspace
any help is appreciated