Vanished date, impossible to contact MTN

I am on an MTN 50+50GB / month data contract. New data gets allocated on the 12th of a month. A few days ago my data balance was 84GB. I rarely use 50GB per month and with rol***** had 94GB on 12 August. A few days ago the balance was 84GB. Last night it was 14GB. MTN does not give any usage statistics to check. It's impossible to speak to an agent on customer care no. 135, you have to select option 0 for that - the response remains: you have not selected a valid option! I had the same problem in the past and at last got an MTN response through Hello Peter