No notification- TELKOM

Good Day. I have been a loyal customer of Telkom for almost 6 years. After taking out my 3rd cellphone contract i noticed that im not really benefiting from the package as promised. However with having a WIFI plan in place i never really worried with my data/airtime/sms package. But recently my contract ended and i wasnt notified that i am due for a upgrade or should cancel my plan in store. This resulted me into owing 6 months premiums and are now being threatened to pay the full amount. Could you please assist as i wasnt notified properly.