Worst cellphone contract ever

Telkom lost the phone they had to repair for me as I am on a contract I have been calling the since Feb asking when am I going to get the phone back as I am still paying very month and the storry is they don't know the 3rd party company they work with should pay for it but the thing is it got lost with them I'm tired of calling am begging to get the phone I'm paying for back Noone what's to help me