Byju's — Pin validation

Address: mohadinagar, mirjanhat, bhagalpur, 812005

I have brought a byju ias tablet program, I wasn't using it due to my academic course but when at last I opened it, then it asking pin validation for login, it been over 1 month, everyday I tried to contact them but they are just postponing the dates. My email id is [protected]@gmail.com, and registered contact no is [protected] with registered name mayank, I just want them to solve my issue.