MTN gave away my number without notification and I cant get hold of a call centre agent

MTN gave my number away as I moved to a pay as you go on this number and did not recharge every month. They did this without any warning to me. I tried to call the contact centre but the automated response keeps asking me to insert this number into the system before I can be redirected but wont accept the number and therefor keeps asking me for the number and I never get transfered to a call centre agent. I am departing overseas in 10 days and have no access to my phone number.