No Huawei Modems

I have not had internet for just on a month. Was first told it been softlocked as im over my uncapped limit. Reported it on the 4/2 that its not working. Tecnician was here today and informed me my modem is faulty. I purchased a huawei modem on the 19/5 and had to exchange it on the 21/11. Not even 2 months later this one also faulty. Went to Greenstone Mall today and they informed me they dont have stock and dont know when they will receive. I am paying for a service which I am unable to use. I would like to know if Im going to be credited for this and when can I receive a new modem. My wifes work is dependant on the internet and its costing me now to use my 3g. I need this problem to be sorted out ASAP!!