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I noticed on my bingo page it says I received 20 free facebook credits to buy item on my favorite games.  I was told I needed to purchase more credits in order to get the 20 facebook gave me.  I purchased 50 this AM--the upper right corner says I got 50 + the other 20 credits.  But where the regular credits show on bingo--I don't see them.  What do I need to do now in order to get them??