Called number back and got voicemail mailbox. Dodgy as. I’m thinking it’s a ghost number for overseas scammers

Answered was quiet for about 3 seconds then overseas person said good afternoon madam and how are you today. I hung up. I've had a number of telemarketers call me for solar panels this week for some reason. This number has rang a few times, then they call immediately afterwards with a private number. You try to call back and it's a robot message bank

Caller: Someone from a solar company

f*ckers called me on a Saturday and I made them hang up in the end. Tried calling back to hassle them and got a full message bank

dodgy, hangs up as soon as you answer

Caller: No idea

Several missed calls from this number, when you call back it goes to message bank, and says message bank full. I’m a nurse, on shift work, so really don’t appreciate these stupid calls late at night!