Lack of customer service

I attempted to change my email address using the self-service functionality on the website. After several attempts, with the site reverting back to the previous email address I called the call centre. The agent agreed to change the email address for all my accounts. She did change it for my cellphone account but not for my data contract. I received an SMS informing me that my account couldn't be sent to the email address on record (even though it had already been changed). I rep**** to the SMS for the cellphone and data contract email address to use and am still waiting for my data contract statement. I am extremely dissatisfied with this lack of service delivery and abysmal customer service. I expect my email address to be changed for the data contract with immediate effect and be sent within 2 working days to the correct address