It sounds like you’ve covered all the main troubleshooting steps I would normally suggest: making sure the Luba is properly seated, cleaning the contacts, and verifying the power supply. I haven’t personally experienced this issue with my Luba Mini, so I’m afraid I don’t have any additional solutions to recommend beyond what you’ve already tried.
At this point, I think it would be best to contact Mammotion support directly, as they’ll be able to provide more in-depth technical assistance (accessing logs) and may have specific advice or a service solution for this issue.
Sorry I couldn’t be of more help, but please let me know if you have any other questions or updates!
Best regards,
Mark