Incoming call, when answered the caller hung up immediately

Scam don't answer

Scammer, no message left. Another number to block

I didn't answer, but dialed the number later and it appears to be an organisation known as "MY CHARITY.com", based in USA. Another nuisance group seeking money I suspect and probably best avoided.

Nobody. Dead air.

when I answered they just hung up

Getting a few calls that don't leave a message.
Phone IDs it as "potential fraud"
No idea who as I'm not answering.

call centre