Nibble Group Harassment

This company has been harassing me for months on behalf of Finchoice. I've requested their banking details to make the payment and they are not willing to provide any banking details. I have requested that they forward me the settlement letter via email because I need proof of the amount I am going to settle. None of my requests have been met but I'm being harassed daily. My question is who's going to pay for the telephone costs because everytime they call me, they add a fee.?