'DataFrame' object has no attribute 'append' error

[danibiru]

Hi, how are you? Maybe You can help me

When I was trying to run critical point apprach file, at the end before saving to Excel, there was some error that I couldn't understand. The program failed to store the value since there is no attribute 'append' error. I have checked the Pandas Doc and change with concat, but it seems not to be working. Could you please have a look for this issue. thanks

pandas-dev/pandas#35407