MWeb LTE with VOIP calling is non-existent

I was advised by an Mweb consultant to change my Fibre line to a LTE line, since this would be cheaper and since I would be able to get rid of my Telkom landline and instead use the VOIP service provided with the LTE router. I did so. Unfortunately the Huawei B315s-22 router they sent me did not have the VOIP option in the settings (even after upgrading the firmware). I phoned support and spoke to a specialist who said they would send me a new router. After a week I got the new router and it had the same problem. They also sent me a bill for the router which should be free. So now I'm stuck without fibre and without a landline. It's also impossible to find the LTE calling rates anywhere online. The reference number was MWB **********