I NEVER RECIVED MY REFUND FROM LAST YEAR I HAD TO CALL THE IRS THEY SAID IT IS FIXED BUT I STILL HAVENT GOT IT WHAT DO I DO NOW

I CALLED THEM CAUSE I GOT A LETTER TO VERIFIY  IM ME THAT NO ONE ELSE FILED MY RETURN CAUSE I MESSED UP AND DONE TO BUT I DID THAT STILL NO REFUND WHAT SHOULD I DO