They Services is very bad

I bought a phone from them; it's been three months. The phone started to give me problems when I called them. They said they would send the courier to collect the phone, but two weeks down the line, the courier came and collected it, and after that, there was no communication. I was busy calling them, asking about the phone, and they told me that they had received it. So I was waiting for the repairs to respond about the fault on the phone, but there was no communication. I called them last week, and they told me that they hadn't received the phone, and now they are taking my pilar to post.