Our toilet did that early this year while we were camping. We just put upward pressure on the floor pedal with our toe for a day or so to stop it. After doing that for a couple of days, it started working correctly. We never knew why it behaved badly for a bit.
Sherm & Terry w/rescue Eydie (min Schnauzer) & Charley (std Poodle)
2015 Jay Flight 27RLS, GY Endurance (E), Days: 102 '15, 90 '16, 80 '17, 161 '18
2006 Ford F350 PSD, 4WD, CC, LB, SRW, Cmpr. pkg, Equal-i-zer 4-p, Continental ContiTrac TR