After sales service terrible from VUMATEL

Signed up with Vumatel and now after sales service is terrible. The fibre line has been faulty 3 x this month leaving us without internet for days. On 2 occasions the line went down on Friday afternoon at about 14h00. Following up with the call centre is a joke and the standard response is that the fault is still within SLA (24 to 48 hrs). It looks like the job card only gets issued to the technicians after the fault has gone out of SLA. In all 3 cases, the fault was on VUMATEL side. If you think faults will be repaired on a Friday (or Saturday) within SLA, forget it.... Requesting the call centre to escalate the service request has NO effect..