When answering this call, the number receives your connection then switches off.
If you then ring it back the message comes up: "this number is switched off or unavailable."
My guess is that they are checking that your number is still active so that you can be targeted for financial scams.
Solution: Don't answer the call.

Been getting a bunch of 07 numbers in recent weeks, previous times I answered it would click and hang up, likely checking for live numbers - so I cancelled this call and blocked it.

Offering a 43% energy discount without knowing anything about me, my current provider or what rate I currently pay. Do yourself a favour and block the number on your phone!

Cold calling energy retailer

electricity crap . I