Hewlett Packard (HP) not resolving my issue

Sir,I purchased a tab of HP,Initially it was working fine,but from the month of June it started giving out the problem,and till now it is giving the problem and my tablet is in service center now also for the 5th time.From june 2015,I've had telephonic conversation with many higher authorities,had enormous online chats and visited service center but my issue is not resolved till now. Day before yesterday i got call from service center that problem is fixed and i can take back my tab and immediately i received a mail stating that tab is working fine. But the serial Number mentioned in email is not of my product but of some printer,whose warranty is expired in 2011.Today i'm going to visit service center again,and if i see that same serial number on my product,should i accept my tab or decline to accept the tab ? and is it a fraud done by HP because on warrant check it is showing different product's warrant which i don't even own. and can i file a case in consumer forum because of the mental stress i suffered from HP ? urgent help needed sir .