ITR 3 FILING AT NEW INCOME TAX PORTAL REG

I AM AN INDIVIDUAL ASSESSEE. I AM NOT ABLE TO FILE ITR 3 RETURN FOR 31-03-2021.I HAVE FILLED MY RETURN THROUGH UTILITY AND AT THE TIME UPLOADING THE RETURN IT SHOWS ME A ERROR MESSAGE AS "YOUR RETURN ALREADY SUBMITTED YOU CAN NOT RESUBMIT IT".TODAY(17-12-2021) ALSO I TAKE EFFORTS TO FILE MY RETURN IT SHOWS THE SAME ERROR.I WILL GO THROUGH THE E FILE TAB AND VIEW FILED RETURNS BUT THERE IS NO RETURN FILED OR NO RETURN IS AVAILABLE FOR E VERIFY.I HAVE TAKEN MANY EFFORTS THROUGH PORTAL THAT IS GRIEVANCE SUBMISSION AND MAIL SENT TO E-FILING WEB MANAGER.THERE IS NO PROPER GUIDANCE OR SOLUTION FOR THIS PROBLEM.BECAUSE RETURN FILING DUE DATE IS FAST APPROACHING.KINDLY CLARIFY AND GUIDE ME TO FILE MY RETURN.