Dear (Legal Heir Name) 
PAN: Deceased PAN, A.Y.:2020-21
DIN: CPC/2020/LH1/108565049 
As per our records, you are the registered legal heir of Mr/Mrs/Ms. Deceased Name. The return/order for the A.Y. 2020-21 for the Deceased PAN has been processed u/ s 1431a on 1-Dec-20 determining a refund. The refund issued has failed and a failure communication has been issued. 
In order to enable this office to release the refund, the legal heir must file online ‘Refund Reissue Request’ in the e-Filing portal. The refund re-issue process can be initiated only if the Legal Heir’s PAN is operative (the PAN of the legal Heir should be linked to the Aadhar of Legal Heir)
To raise refund re-issue request for a deceased assessee. Logon to the “e-Filing” website www.incometax.gov.in (with legal heir Login credentials) >Dashboard >My Profile > Select the drop down under “Logged in as” -Legal Heir > and follow the given steps to submit refund re-issue request for the deceased person. 
Go to Services > Refund re-issue request> Enter the “PAN” of the deceased taxpayer> Verify the assessment year and ensure that they are correct. (If Refund Failure occurs, CPC communication reference number and Assessment Year will be displayed automatically) > click “Submit” link under Response column>Select the one of the pre-validated bank accounts for refund and click ' Continue' > Select Account type and click 'Submit' and proceed further for the Refund Reissue request using e-Verification option or using DSC (if registered in profile). Legal heir bank account details will be accepted at the time of request submission.

NOTE: 
1. The official website for income tax login in India is https://www.incometax.gov.in
2. The Income Tax e-filing portal provides Helpdesk support for taxpayers facing issues or needing assistance. You can contact on the below mentioned numbers between 8.00 a.m. to 8.00 p.m. – Monday to Friday:
  1800-103-0025
  1800-419-0025
  080-46122000
  080-61464700