MTN-Very Poor Customer Service

I have upgraded cellphone contract Friday 10 March 2023. To date 15 March 2023, I have not received new cellphone order. DSV cannot deliver because MTN did not update my contact details as requested. MTN consultants not very helpful, and they are not updating customer details as requested. I have been a loyal MTN customer for more or less 10 years. They are quick to debit bank account but not quick to update details and get the couriers to deliver speedily.