Afrihost disabled my SIM for no valid reason and without prior notice

I am using a "fixed wireless" service from Afrihost called "Pure LTE". The same device Huawei B315 has been in operation for years, but out of nowhere on 1 November my SIM got disabled. Afrihost support told me it is because the device is not on the list of "compatible" devices. This was done without prior notice and now I do not have service and they also refuse to issue a refund.