Why are banking apps in Thailand failing, and should I switch back to cash?

Well, consistent with nothing every working correctly in this country, I've now been stranded twice in 1 week at Rimping while my app fails. Friday, Rimping (in maya) was unable to accept payment from mobile apps from Krungsri, K bank, and bkk bank for many hours. Today, my app continued to freeze and throw error messages while trying to pay. The cashier said it wasn't only me today having problems.

After 5 minutes I had to abondon my groceries and walk to my bike where my wallet was. I've come to trust the banking system here as reliable and efficient so I don't normally carry my wallet on me, unless I'm out at the bars since most of the apps consistently go down for maintenance at 11:50pm every Saturday for some reason.

Thus I've come to the point where I can no longer rely on the Thai banks to provide consistent service, back to cash I go.