Harrassed by recruitment agency

Dreamscometrue

Every day now for over a week I receive calls with a hidden number to the mobile phone I use for agencies to call me on. As soon as I answer I hear a lot of boisterous background noise & they slam the phone down. One day they made the mistake of calling on a voicemail number and I got to see who it was. I only take on contract work and some time ago I told this agency I was not interested in what they had to offer as the roles were generally poor and paid around half the rates of recent roles. Isn't it incredible how childish they are? They obviously have nothing better to do!