duff kids video from Tesco

Hi
I ordered some kids video's on special offer from Tesco earlier this year.
I have brought them out one by one to cheer up the kids (and keep them
still) when they are convalescing from bugs.  All six so far have been
grand - Bob the Builer etc the usual.  However the last one, Brambly Hedge
the Autumn Story, I kept until, obviously, autumn.  Kids have flu so I stuck
it on today and it is totally blank.  It has never been recorded on - the
numbers stay at zero when you wind forward.  I rang Tesco and they weren't
interested.  They said if you don't check them within seven days then tough.
I expected to hear at least 3 months, but thought I would try anyway.

Any advice as to what I can do.  I'm am getting conflicting messages on
this.
TIA
Suzanne