Bad service

We have Fubre with Cell C and Vumatel. There are endless problems lately. Service is on and off due to cable damage for the last 2 months. We reported no service again on Saturday and got reconnected in the evening. Unfortunately they made a mistake. Instead of being connected to Cell C with a 100 mps line we are now connected to Vox with a 10 mps line. Nobody seems to know how that happened and it is not been fixed. We also do not get feedback. Please can you help!!!