Multiple calls - how to stop

Ive had to make a Virgin account to ask how the f virgin got my personal number and why they feel 5+ calls a day to try and sell me utter s is okay, ive had no luck with using an o2 virgin linked account or whatever the f its called. i dont know how this s company works, its all s, just tell me how to get them to leave me alone

[Mod - title edited for clarity]