Hi All, I bought a 2018 crosscity e bike with a dead battery, it had fallen below minimum voltage to charge, I opened up the battery and charged it by the battery + & -, now when I turn it on it either turns on straight away or the display just flashes and then turns off, if you turn it off via the display and then turn it back on it works fine, if you turn it off via the battery on/off and then try and turn it on again it just flashes one battery bar and then turns off, I have tried unplugging the BMS board and plugging it back in after a few seconds, I've tried electrical spray on the switch, I've short wired the switch to rule that out but still it will not switch on properly, any ideas ?