I'm convinced my details are amongst the thousands stolen from Talk Talk last year. Since early this year we have been plagued with calls from India claiming to be from Talk Talk and that our computer has been hacked. We have had hundred of these calls from a variety of different numbers - some of which are actually UK numbers - which we subsequently block. However our phone only had the memory to block 35 numbers so we had to clear the memory and start again.
Unfortunately, I accidentally blocked my elderly mother in laws number and was unable to unblock it - it must have been a fault with the phone- so have now had to buy a new set of phones!
Talk Talk are pretty useless. They have guidelines for dealing with these calls but the bloody phone still rings, if it's not an already blocked number. Most of their advice is common sense anyway.
Mind you, if I am not actually busy, I pretend that I am a child and I am going to fetch 'Mummy' and then I leave them on hold. Sometimes I ask them (in French) if they speak French - it confuses the hell out of them. Oh well it gives me a laugh....and if I didn't laugh, I'd cry!