Change of name in co-op society records

A lady own a flat in a co-op housing society in Mumbai which stands in her  married name.

Her husband expired and she has since re-married.

She has changed her name and her son's name by way of Government Gazette.

She has applied to my co-op housing society to change the name in the share certificate from earlier married name to current name.

However the society managing committee refuses to effect the change on the basis of the gazette notification.

Kindly advise the procedure to be followed.