Their Bad service and ******

Pest control Specialists SA Sandton didn’t do a great service at my house at all. I paid R1840 and they came to do whatever they did but after few days they ****roaches were still in my house till now. I told the guy and he said I should do the EFT ASAS before he reported me for not paying and gets me blacklisted. Then He told me to add more the a thousand Rands for them to come again. So the question is, what did they come to do? And why ***** someone like that? They better come back and finish their work properly.