BAD SERVICE PROVIDER FROM THE INSURANCE

i getting harassed by one of your service provider by the name of Warren from domesticare after I made it clear I dont want them at my property anymore. After they repaired my geyser the ;last time I experienced a leak on my geyser I logged a call and they were sent back and according to them they replaced a pipe, please how does an solid pipe jsut start leaking and warren called after the repairs was done and he said they had to replace a small pipe and owe R150 and a week later i got an sms that I owe them R550 for what for I dont know. I was not home when they did the repairs and I cant confirm if what they say is true and I dont trsut them since that day. They replaced my geyser gasket which only lasted 8 months, and when i confronted them about this when they were given the recent order to replace my geyser he himself said he will cancel the order, when I asked him hoe come his so called new gasket only lasted 8 months. he was in my property for less than 30 minutes. what if the leaking pipe after the repairs was because of poor workmanship . your service provider is harassing me and sending nonestop sms's . I will not accept this, please deal with it.