atrocious "customer support"

i requested for a line change on the 21st of last month BEFORE THE BILLING RUN......

Guess what it never happened. Today i get a mail from requesting payment for the old line, i try to get in touch with 5 time to no avail either the put the phone down or im on hold for 45min. Their customer support is non existent and their billing department when they answer the phone is *********** and say "we can have a manager phone you back" im still waiting for this to happen.