Caller: Telemarketer for charities

I didn’t answer, but tried to call back and got a message saying it’s a company (didn’t catch the name) and they call on behalf of a number of charities.
Not scam, but most likely asking for donations

Number- which has called me twice in recent days- not recognised and not flagged by my phone as spam. I did not answer the call. Their call went to voicemail but no message was left. I assume this is some kind of spam number.