I would suggest that it is the battery.
The on board voltage indicators are not very accurate as they are not calibrated in any way and I feel that if you check the battery voltage with a multimeter, you will find it lower than indicated.
The mover needs a very good battery to allow it to work, the manufacturer recommends 110ah, but more inportant is the state of the battery, its Cold Cranking Amps figure, and whether that power is being delivered on demand , for which a Drop Test would be a good idea, also as an indicator is to put a multimeter on the battery terminals and see what the voltage does when the mover is operated (with the rollers OFF the wheels!) the voltage should initially drop a little but recover quickly, if the battery is good.
If not, the voltage may well drop well below the required needs of the mover.and stay low.