Why is the amount sent back to the IRS less than the amount my refund was for?

i filed online and asked for direct deposit and i entered the wrong account number.  the IRS approved my refund and it was sent to turbo tax acct on 2/27/15. It having the wrong acct number, it was sent back to the IRS, but when returned to the IRS it was for a lesser amount.  I would like to know where the difference in money is?