Harassment

I have a Mr Price account .. and they are the worst company when it comes to payments .. yes I have missed two payments due to some other payments that I had to make and I also have had no time to getting around to make the payments as I work in a hospital .. first I have asked them to NOT contact me at work as I work with sick people and my boss doesn't like personal calls .. I have had in the last two weeks 10 different people call me everyday .. and I tell them the same thing over and over .. it actually gotten to a point where it's harassment!!! I told them I will make payment when I get chance and then 5 minutes later someone either calls me. It's getting to a point where my boss is probably going to fire me !!!