Mtn contract to prepaid

Extremely difficult to get hold of the cancelations department. Called over 20 times as my contract expired on the 1st. Needed to then dial 135 in order to stop the contract and have the number changed to prepaid.

I follow the prompts however the phone then hangs I immediately after I select 0 for the service champion.

Baffles me to why I can't have this cancelation done in store or better yet via email.