Hello Saumya

Yes , add on course can be changed  in Patna Women 's College but only if there is a seat in another subject.

You need to write application to the sister regarding the change of add on course .

You need to visit the college for that and ask the concerned authorities about the format and procedures regarding that.

You can also try to contact through email and call but it is better to visit in person.

Thankyou !