Poor service

I entered into an agreement with MWEB for an uncapped 10Mbps line. The service has been going great until now. The service is absolutely poor. We cannot use on more than 2 devices, a 45 minute series takes about 75 minutes to watch. I have lodged a service request with them with no success. The technical support team set up an appointment to call and assess the issue but failed to keep the appointment. From 1 January 2021 they increased the subscription but the service is absolutely poor.