Hello. i have problem with my battery. My battery have good connection and don't have any corrosion because i bought my mavic air combo 2 days ago. second and third battery working well. How can I fix it?

Have you updated the FW recently? If so, did you miss one of your batteries?

Hmm.. I think no, but how can I updated my battery? Maybe I'm doing some wrong..

I updated FW mavic when "the bad" battery was be inside my mavic

My MA was stuck on the 39th floor rooftop for a week. It was there over a week under the strong sun as well as heavy rain. When I managed to got it back, I've got same error with all my 3 batteries. What I did was clean up the battery contact on MA with DW40 and it back to normal. As for your case, maybe you could try to clean it up with WD40 on your problematic battery.