Samsung - Samsung Active 2 Watch Defective

I have purchased samsung galaxy active watch * *g lte variant. service center has given me three times replacement which had same defect of heating while making lte calls, i had shown them evidences and they have accepted it as well. now its becoming mental stress for me when they take * month for replacement, this is * th replacement and * month has already crossed and no one is taking ownership to close and resolve my issue, neither they are ready for complete reimbursement, they say we will give only **,*** and **,*** will not be given since **k was voucher. even if its an online voucher, if it has to be reimbursed it has to be complete reimbursement or they have to provide me good working watch, i m tired of multiple followups and its been * months