Trying to split pay my bill for a week

I have been trying to split pay my bill for the past week over internet in Bryce, Utah where AT&T coverage is almost never 4G, public access internet is overloaded and slow and having a data plan is basically useless. I have timed out and encountered multiple errors, the last one said the system was down and couldn't process my request and now my account has been suspended. I am beyond frustrated and need some help.