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Hello, I live in Canada. I had purchased a 10$ facebook credit card. I redeemed it. It gave me 96 credits instead of 100. I looked through my account and my payement currency was on USD instead of CAD without me knowing.. I lost 4 facebook credits, it might seem cheap but I wanted to buy something that was for 100 credits... And now I can't. Is there a way I can re-gain my 4 credits?

Please help me