Plugin settings page Blank after moving server

Things i did by order
–I moved to a new server
–enabled the plugin
–settings page worked, but i forgot to install ffmpeg before uploading multiple videos.
–i installed ffmpeg but forgot mp4box. tried the convert test in the settings page.
–installed mp4box but i still got an error saying mp4box wasn’t found. i think ffmpeg was ok? im not sure.
–i tried a new mp4box path “/usr/bin/”.. correct & old path was “/usr/local/bin/”.
–then i got the blank page after saving.

tried to reinstall both ffmpeg & mp4box but im still getting the blank page. any ideas why this is happening? how do i reset the settings of your plugin? maybe that will fix it?
the queue page is missing btw. im getting this error
(“Sorry, you are not allowed to access this page.”)