Where's My refund?

I filed before Feb. 12th and my return was accepted on Feb. 12th however it is now March 18th and I still don't have my refund? Does anyone know what's going on? I have tried calling the IRS but can't get trough. I look at the track my refund on the IRS website and it says, "Your tax return is still being processed.

A refund date will be provided when available".