Similar issue here, after a missed call I googled it to find its apparently a genuine virgin number*. And again they want information off me which I won't provide as they should be able to provide something to prove who they are. Yet they keep calling all the same despite me either hanging up or saying "not interested stop calling".
* I say "apparently a genuine virgin number" with regards to 0800 052 1251, but how sure can we be this is genuinely virgin media?. I'm asking and questioning that as every time I get a call from this 0800 052 1251 number within a certain period (usually an hour) I also always get a call from a number +8001836411. Research indicates (from this forum I think) that whilst that also is a "genuine" virgin number, that number would never be displayed like that and it could be a spoofed number and people should be careful of it.
If that's true then how sure can virgin be that both numbers are not spoofed and unsafe?. Because it's been reported countless times by people that the 0800 052 1251 caller is often highly unprofessional, of poor understanding & won't take no for an answer and keeps calling even after being asked not to. And with this second number always calling at the same time that would never be displayed if genuinely virgin, well it's certainly an issue for concern on both numbers.