IS BOOK BAZZAR THE ONLY PLACE THATS PREFFERED FOR SELLING CREDITS? ANY WHERE ELSE?

Book Bazaar in the place I have always sold credits.  Do a search (title only) for "Credits for sale".

Its the only place that you are allowed to sell credits.

eta: On PBS that is.

Your price might be too high.  I used to have no problem selling credits for $3 but now the going rate has lowered.  I see people offering them sometimes for $2.50! I would never go that low.  It seems to be more common in the $2.75-$2.90 range. 

Yes, the BB is where to post.  You are on the high end (I also used to sell them easily for $3 but the price has dropped to my grumpiness) so you have to have patience & you might not get anyone to buy anyway, since they can get them for less if they look.  I agree that $3 is better deal, and the only reason I'm willing to go lower is because I managed to get people to order multiple books for a while.

You might also do better if you didn't post the same thing over and over and over--it's annoying.