Legal heir claim for morgage property refuse to pay back loan and loan on wife name husband died

Me and my husband bought a flat in chennai. Loan in my name and husband was a vo borrower. Husband dies due to COVID, now outstanding due iam paying for past 6 months.his mother (legal heir eligible for 1/4th share) claims for property but without paying anything.She got all the settlement from my husband's office as no nominee name was updated by him. Shared based on legal heir.