Phone rang. I picked up and said hello but no answer. Tried to ring back but line continually busy. Maybe tellecaller.

Has been calling for 3 days (9 times in total) no message left.I don't answer unknown numbers.Probably scammers as anyone else would leave a message

This number has been calling me several times a day, not leaving a message. I phoned it back today and got an automated message saying that it was a survey, and asking me to answer some questions.