Hua Hin was the same.
I ran into a Thai friend yesterday at Market Village - he was withdrawing cash from his bank, complaining that True was down and he could not use his phone to make purchases at shops.
And there are those who wish to kill off cash?!?!?
Having lived in a cyclone-prone area of Australia for a few decades, I know for first hand experience, when a "big one" hits, and electricity is out for a a few days, or a few weeks in some areas, mobile phones are useless.