Extremely rude customer service agents and no communication

If I could, I would give them a zero rating. I completed my payment after 3 months and after I did, they continue to SMS and call me. When I call to find out what exactly is going on, they take forever to answer calls and are extremely rude and not helpful on the phone. One lady even said "Clearly you do not want to listen today so I will email you later so you can see your statement". That was more than 3 weeks ago and I am still waiting for that email, yet they are able to call me everyday, different agents by the way, asking me when I will make payment.