MTN RETENTION DEPARTMENT NOT EASY TO GET HOLD OFF

I have a Student Data contract at MTN, I have never used the contract as It was approves late. I went to the store to cancel the contract i was told at the shop they cannot assist me as i must call 135 and cancel my contract myself. Ever since till current date i have been on the phone the whole day.i have spoken to countless operators saying they cant help me only retention department can help me. I frustrated because if been on my phone for hours on end listening to an annoying tone. What is weird is that when i choose the option on the operator to upgrade phones are answered.....I mean the company has made it impossible to cancel the contracts in store, but did not make provision to help customers on the call line with cancelations. MTN IS ANNOYING!