MTN and FNB

I purchased 1gig of data from my fnb app R160.00 was debited from my account but data was not allocated on my phone I called mtn which said i should call fnb I spent over R170.00 to be on the phone with FNB I want my Data is there anyone who can help me. Fnb said the transaction went through so it my service providers fault . Who helps me in such. I am not buying another data my work is on stand still.