Thanks for using the Apple Support Communities. I understand that you appear to be having issues with the Other portion of your iPhone storage. Generally, Other data should be cleared out as needed by the operating system, as outlined here:
About cached files in "Other" iOS storage
Cached files are created when you stream or view content like music, videos, and photos. When you stream music or video, that content is stored as cached files on your iOS device so you can quickly access it again. iTunes categorizes cached music, videos, and photos as Other instead of actual songs, videos, or photos.
Your iOS device automatically removes cached files and temporary files when your device needs more space.
How to check the storage on your iPhone, iPad, and iPod touch - Apple Support
If that is not happening, you may want to try backing up your iPhone to iTunes, then restoring that backup back to your iPhone:
How to back up your iPhone, iPad, and iPod touch - Apple Support
Restore your iPhone, iPad, or iPod touch from a backup - Apple Support