'str' object is not callable

After inputting a string value, I’m not able to use it again as in not able to apply any operations to it neither am i able to change its data type. I continuously get this error that ‘str’ obect is not callable.
Can somebody help me out?

Hi, Nikhil.

May I know which concept or topics you are referring to or where you are getting this error?
generally, this error occurs when there is a mismatch in data types.

Send me the screenshots for this. I will look into it.

All the best!