In case the Kodi best build is not working, try carrying out these troubleshooting tips:
Clear cache- Clearing the cache removes temporary files which may be causing problems.
Update build- Update the problem build because some add-ons usually stop working.
Check internet connectivity- Slow internet speed may cause either buffering or streaming errors.
Reinstall the Build- If all else fails, uninstall and reinstall the build.
Use a VPN- Stream with Kodi through a VPN as some ISPs may block these streams.
Please remember, if all these tips fail at salvaging the build: then basically because it's beyond salvage, it's going to need reinstalling from the Best Kodi Builds list.