*** customer service and general ops

I've cancelled my fibre connection (lots of reasons) trying to move to a proper ISP. They should have released my line yesterday (after serving all my notice periods) so that my new ISP can connect me. I've been fighting their call centre (6 calls in 24h). But they are utterly useless. None of them can do anything about it. All they can do is "log" it with another cancellations / retentions department. No managers, QA, team leads, COO's, like in no one that I can escalate to. Everytime they promise me it will be resolved within 2h, then nothing.... I feel so bad for the customer facing staff working there, real lack of leadership and systems....