Internet SA is ****ming us

I have requested internet SA to install WiFi at my mom's place. I have the payment but they have delayed to come and do installation. At the end they came after so many complains, after that the network was super bad, I informed them sevaral time and said they will send a technician that never showed up. Today I did a follow up again and I also took a picture showing them that the Ariel that they put it's very old. They feedback I got is that it is their property if I don't want their service they will send technician to uninstall it