I don't usually have a problem with incoming marketing calls. I have a landline, however there is no phone connected, the line is only for my broadband. They can call that number as many times as they like, I'm never going to hear it ring
If they get my mobile number, I have another simple solution to the problem. I don't answer any withheld numbers or 0845/0870/0871 numbers. If the person calling me is a genuine caller who urgently needs to speak to me, they can leave a message and I'll call back
