Jhnee1

Arctic Spa (Tub) was turned off but left full water for a few weeks then I drained it and fixed a leak. I filled the tub and turned it on and now have a flo error. Spa has only one pump and is 5.5 years old average use is once a week by my wife. Now pump won’t come on to heat water. Spa worked fine prior to that except for leak. Checked there are no obstructions, all main valves are open, filter is new and I even removed filter to see if that would work. I have also turned power on and off at breaker a few times. Every now and then pump tries to start and I can hear a hum for a few seconds then it shuts down. Any thoughts how to fix.