Wrong deposit of TDS - Urgent

Dear Members

What are the possible solutions for :-

1.       If deductor has deposited the tax in wrong section say 94C instead of 94j, how can he rectify this mistake? Can he file the TDS return in right section i.e. 94J? if not than what is the right action that is to be taken?

2.       If assessee has wrongly deposited the TDS, how can he claim for its refund?

Thanks in advance..