Migration

I have a 20gig data contract, 5 gigs during the day and 15 gigs at night. I logged a call to migrate my package at the end of November as there was a special for 10gigs during the day and 10 gigs at night for R299. I have not been contacted since then. The promotion is now done and I am annoyed as I have had to call the call centre to be put on hold every single time to find out why the migration did not take place. I have asked for a manager to contact me but its been 2 days later and no one has called me back. The lack of service is shocking!! Please can someone contact me and let me know how we plan to get this resolved.