Mivi — Replacement of faulty product

I buyed product from mivi and its stop working then I send it for replacement and this is second time I sent it back n now its been 1months they are not returning my product n nobody is responding related to my product mivi is a fraud company and the worst part is its using Made In India name to fool the customer plx take strict action against mivi and when I posted this issue on mivi twitter they block me