Sufiyan From Thane want legal help in Immigration

My Indian sister is married to Mauritian national, both are muslims by religion. they married both traditionally and legally in India this year. Now, my sister is required to register her marriage in India, but the local municipalty here is asking her to get nikah nama and court certificate attested by Mauritius embassy.
Please advise if this can be possible ? My brother in Law is in Mauritius and is awaiting all documentation work to be completed before he can come to India.
When my sister visited Mauritius this year after her marriage on 24 February, 2022 she produced all relevant documents to immigration officer in Mauritius to get spousal residence permit to stay in Mauritius with her Mauritian husband but she was told the document cannot be accepted, though that court marriage certificate is legal document of Government of India.
court marriage certificate issued by Government of Maharashtra that has marriage officer stamp, and that certificate has notary and apostille done with Indian government stamp on it was provided to immigration officer but the officer refused citing it should have ‘registered’ word written on it instead of soleminized.
Sir, the document is valid document issued by Government and has legal acceptance all over the world. That document cannot be changed for any word or letter.