Caller: ‘Brian’ claiming to be offering ‘comparative’ electricity deal.

‘Brian’ and his ‘supposed supervisor’ could not provide any legal reason for having the phone number they used to call me.
The phone number they called has no possibility of being linked to my electricity account and their ‘fishing’ type of questions were simply obvious that they are a group of scammers.

I didn't pick up because I never do when I don't recognize the number.
No message left --> spam call sign #1
Called number --> inactive number --> definite proof of spam call

Noisy call centre background noise, caller with difficult to understand accent, questioned power for my street, perhaps a power company?
But then why are there no results during search of phone number?
So scary that phone numbers do not have a record and cannot be traced, especially when we are warned there are so many scam calls.