Spam, fraudulent calls from Virgin.

I've been getting calls nearly every day now from this number 08000525306 & it shows up on my phone as Virgin Media. I've been unable to answer until today & a guy was on the line. Asked to speak to me, gave me my full name & even told me some of my package I had & how long left. And he was calling to see if there's anything they could offer me or discounts on offer, so I needed to just pass the security phase to proceed. When I said I wasn't interested in adding anything or changing anything, he just hung up on me. When I called the number back about 5 minutes later, it went to Virgin Media & the automated voice said, it looks like we tried calling you today. 

So, is someone in one of Virgin Media's offshore call centres acting maliciously? Because I googled this problem & there's a site for identifying who called you & a lot of people have been getting the same thing. 

So, Virgin better get to grips with this, or better yet, stop having your call centres abroad in places where telephone scamming is rife.