I had a similar issues:

On Thursday, I got my meter with a dead battery, had to replace it and then it worked fine.
Friday morning it was working great until I got that forced firmware update.
After that, the meter was unusable, my phone would connect and them immediately disconnect from the meter.

I saw on another thread that I should try reinstalling the app, power cycling the meter, restarting my phone, etc. I tried them all with no luck. I figured I would just wait for the next firmware update.

Then, I tried the meter again this morning, and it’s working. I’m not sure why, but it randomly started working…