With input from furas, I added a line of code which worked. Below is the code.

I still include this line in the data cleaning function:

f1['Date'] = pd.to_datetime(f1['date'])

But if I add this line of code immediately after:

f1['Date'] = f1['Date'].dt.tz_localize(None)

It removes the timestamp and leaves me with only yyyy-mm-dd

Thanks, as always, good people of Stack overflow