Just died down

Just starting dying down on revs and down shifting to keep revs up but it wouldn't rev until it died. Then itd 30 on bottom left of speedometer like maybe a code 30. Shook the bike and beat on it and trying pop starting it and even hitting the electric start it wouldn't even try to start. So after messing with it for a while the red engine light came on and it started up and it worked fine until I got home.

Any ideas?

Code 30 is lean angle sensor.
There s a youtube video, however I cant watch it at work, but perhaps its helpfull:
https://www.youtube.com/watch?v=oD_oyqBH_os