A friend of mine had the same thing happen a couple of weeks ago, he is a major tech and read the guy out, chapter and verse. He couldn't track the number either.
Indian sounding guy claimed he was from my isp (talktalk) saying I had problems with my internet.
connection (I don't.) Funny thing is, I was expecting a call from talktalk on an unrelated matter.
When I said I had no problems he insisted I had because he was from talktalk. He then asked me in a snarky manner if I was a tech, at this point I called his bluff and hung up.
So, talktalk customers beware! A look up only revealed a partial number 0401. I googled that and it was confirmed a scam. So, just a heads up.
Dafydd.

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