CellC just want to sign contracts - no service after

We decided to switch over from one fibre service provider to CellC, and this has just been a huge mistake from the beginning. It took more than 2 months to change over the configuration after we signed the contract. And when that was sorted out, we were billed for a month we didn't even have service yet. We were also promised one month free and we didn't get that. So now both ladies we had contact with just disappeared. I can't get hold of either one, the numbers don't exist anymore. I can't get hold of anyone that can help me and everyone that sent a mail is just not replying.