Poor business practices

I have been a Vodacom customer for more that 20 years. about 7 years ago i took a red advantage package for the purpose of Limitless SMS service. For 7 years i received limitless SMS services however on August 12, 2019 my service was disconnected because I reached a fair usage. This was never applicable and i have been sending the same amount of SMS for the past 4 years. I was contacted by Vodacom around a year ago and they offered me to change my contract as they can see we do not use the 700 min or the 2 GB data that is with the contract but we declined.

We were not given any notification with regards to this and my income depends on this service. nor is it viable to pay Vodacom after 7 years R450 per 2000 SMS that will cost me to close down.

The customer care consultants are not really of great service as they say the fair usage policy has always been in place.

My question thus is if the policy has been in place for the duration of this contract how come we only experience it for the first time this month.

They don't even try to accommodate their customers who has been using their services for decades. Even if they charged me 0.11c per message as per my current contract it would be acceptable seeing that we don't make use to the data or the free minutes that is on the contract.