Bad service/passing the buck

Hi. <br> I recently paid for my outstanding amount for my contract Samsung phone, which was blacklisted due to not paying on time. I paid the full amount owing but my phone is still blocked. I called them several times and all they do is put me on hold for 40 min and after that they said their system is offline. Went to a walk in outlet in GAlleria &they told me they can't help me as they phone is not linked to their contact centre. I have been moved from this dead end to another with not help. I don't have a working phone right now. I'm really fed up with this service.