Refund claimed on unknown turnover in form 26as in the a.y 2018-19 can be return to the it dept.

I claimed a refund for the turnover of 60 lakshs in 26as i.e. 60 thousands out of which 20 lakhs is only my turnover.  40 lakhs turnover is posted wrongly by a company in my PAN, for the A.Y 2018-19.  Now it mismatch with GST turnover.  I want to return the excess refund claimed by me on 40 lakhs turnover to the Income tax department.  But time to file revised return has gone.  Is there any solution to return the amount to the IT department, Pls suggest.