Dell computer ownership transfer issue

I bought an used computer from Bestbuy outlet and the manufacturer warranty is still available. I am trying to raise a support request to Dell and they asked me to transfer the ownership from previous owner to my name in order to service the request. I didnt know the previous owner name and I contacted Bestbuy customer service, Geek squad, Best buy store as well and they told that they could not provide the customer information due to their privacy rules. They asked me to contact Dell which they have to help me change the ownership to me. Dell customer service acknowledge that they sold to best buy but the service tag is associated to some other owner which they want that. I am in a scenario where no one is helping out. 

I went through this forums and tried others got it corrected using below thread.

http://en.community.dell.com/dell-groups/new-to-community/f/3511/t/19257087

I did this 10 days back and since I didnt heard from Dell, i have to contact them back to find out that they declined my request. I want your help in resolving the issue as soon as possible as I have spent more time on this.