Key error: Store In rossman_data_clean.ipynb

Part 1 (2019)
1

Hi,

In rossman_data_clean.ipynb, I got a key error:Store when executed below lines of code

df = df.merge(bwd, ‘left’, [‘Date’, ‘Store’], suffixes=[’’, ‘_bw’])
df = df.merge(fwd, ‘left’, [‘Date’, ‘Store’], suffixes=[’’, ‘_fw’])

What could be the reason?

Before these lines of code we wanted to drop Store indices grouped together in the window function.

Regards,
Badaristrong text