Weirdly I am having the exact same problem on my Zappi, same BMS errors in the Tesla, I spoke to MyEnergie this morning and they are replacing the zappi unit, Tesla analysed the issue over the last few days and said they were seeing proximity fluctuations of -0.3v to the proximity signal, like you mine would work sometimes and not others typically it would run ok if i charged during the day, as soon as scheduled at night bingo would come down to it having added a single kwh to the battery and the Tesla Logo light would be red.
Good to know. Did you have to go to Tesla or could that analyse remotely? I haven't contacted them yet.