try resetting the BMS. Instructions under tube battery installation :
" If at anytime you are not getting power or the LED's on the battery are not working this means that the BMS has tripped. Simply leave power switches on the battery and handlebar in the on position and unplug then re-plug the power cable. This will reset the Battery management system inside of the battery. If this method does not work, leave all switches on and plug in the charger, this will also reset the BMS.
Also, cannot stress the importance of good connections. Only took me 24 hours to learn that lesson the hard way. Mine behaved the same way as yours before it finally fried for good. Loose connections to the Hall Sensor or using the throttle to power up hills or start from a dead stop can all fry your controller, be careful.
What I did: I ensured all wires/contacts were fully inserted into each connector and taped them all together first so they will all move together, then taped that to the connector itself when fully inserted to prevent them from backing out. I did this with all of my connections methodically and after plugging each connector into it's mate, ( makine sure all pins and sockets lined up with no forcing involved ) proceeded to tape the connectors together so they can't back out either. I have had absolutely no trouble since.
By the way, if you are skilled, you can terminate anderson powerpole connectors with a pair of pliers, a pair of channel locks and the right sized cotter pin, straight with a small space pried to size to fit around the wire insulation but still inside the connector end. I use the cotter pin and the regular pliers to drive home the crimped wire/terminal end into the back end of the connector housing while holding the housing just right with the channel locks ( not too tight or you'll marr the slots that attach the andersons to each other ). It takes skill and I had a 40% success ratio meaning I ruined a bunch of connectors, but now I can almost do it right "every single time" ( voice of Miss Swan - Mad TV LOL ).