Poor service

The african bank consultants provide wrong information to the clients, last time i was told when i need to settle my bank they will give 5% discount, now today when i need to settle they tell me that they can't give me the discount. Second; last time i told that when i settle the balance before the 25, there wont be any interests added, now today when i need to settle the balance, i am told there will be interest added. This is a **** or misleading information. these people are failing to do their work, there is no consistency, i have been holding on the call for 30 minutes, i am using my airtime. still no help, i need my airtime compensated!