Bad business practice

Fridge was icing up and not staying cold. Compressor was constantly running. A guy called Mike came out and replaced the Thermostat, regassed and fixed an apparent leak. Now after paying them R1200 (via ewallet and I never received an official invoice) the problem still exists and they have not made an effort to come out again. Everytime I ask for a time when they will be able to come back they either don't respond or they give me a time and then never show up.