Nuisance calls

[Spike1]

This week I have received around 4 calls per day from mobile numbers that I do not know. What I call it back it says that the number is not recognized? How can they call me then? All the numbers are different. How can I stop this?

[O2EmmaLouise]

Hi Spike1,

I've been receiving the same sort of calls recently. It seems to have increased over the last few weeks.

What phone do you currently use?

With certain models of phones, you can silence unknown numbers so they are sent straight to voicemail and appear in your recent calls list. 

[MI5 · Accepted solution]

@Spike1 

O2 help here https://www.o2.co.uk/help/safety-and-security/unwanted-calls-and-messages 

They are scam calls with spoofed numbers.

Explained here https://www.ofcom.org.uk/phones-telecoms-and-internet/advice-for-consumers/problems/tackling-nuisanc...

[Spike1]

I have silenced unknown calls and just block them. Thanks for the info about spoofed numbers, amazing what they can do!!!