I am having some problems and would really appreciate some help.

I bought a Tivo Series 2 with lifetime service on ebay. The seller said he transfered the lifetime service to my name. I received it in the mail, and it worked perfectly. I went through all of the setup steps, and all were succesful. Then after about three days of use, I was recording a show, and all of a sudden, it froze. The unit was not responsive to the remote, and after waiting and trying to get it to unfreeze, I had to unplug it. Then, I waited thirty seconds and plugged it in again, and it would not get past the Welcome! Powering up screen. Then I left it unplugged overnight, and I got the same result when I plugged it in the next day. I then decided to open the cover. I knew that I didn't have any warranty left so I thought it wouldn't matter. I made a cd to test the hard drive, using sea tools from seagate, because I had a maxtor hard drive. The drive failed the quick test, so I assumed it was dead. I then proceeded to purchase another hard drive. It was the exact same hard drive model, pulled from the exact same tivo model. I thought that this would be perfect. When I connected this hard drive to my tivo, it started up correctly, and I was so happy. But then I realized I had to activate the lifetime service again. When I went to system information the tivo service number said not available and was all zeros. I then tried to go online and activate it and it said that the service number was already activated. But the thing is my tivo hard drive isn't recognizing a service number. Is there any way I can get it to do that? Thanks for any help.