I have had my Sundance hot tub for over a year. Got it from a friend so no idea of model or year. First I have ever owned. Has worked great for the whole year until now. Flo error came up. No buttons will work when error is on. I removed filter, but error did not clear. It is a new filter. About a month old. I cleaned it anyway. I used the hose in the filter outlet to try and check for airlock. Flo disappeared after a few minutes. Turned on all pumps. It ran for 20 min, but when cycle ended, Flo came back on. I repeated the same hose method and again, Flo went off. Ran through a 20 min cycle (after replacing filter). On second cycle, I turned off one pump. About halfway through cycle Flo reappeared, but jets and heat stayed on until end of cycle. No buttons would respond. No problem with heat at all. Any help?