Payment direct Sucks!

I received a loan from payment direct of $200 and I couldn't pay back in full so they took the $89 out of my account which I was ok with. The following week the same thing occurred .. The following week I was unable to give them anything because i had more important bills to pay rather then pay them. But now i feel like i shouldn't pay them anything because how rude they are to me over the phone and leave very unprofessional voicemails on my phone. Besides that they harass me everyday on the phone and threaten me about them taking matters into their own hands and taking some kind of legal action. Is this possible for them to do ? How can I go around it? What if u don't pay them back ? And I heard this was some kind of scam anyway? Someone inform me on payment direct please !