Resume is not wokring for transcoding

I have Samsung SmartTV UN60JS7200, Galaxy S7 and xpenology NAS.
It is working fine to play back from beginning movies in TV and beginning/resume movies in Galaxy S7 but when resume in TV, Plex is stop after playback while 0.1~1 seconds for transcoding and direct streaming.
And then TV is not working to backwards. TV is only working to finish Plex app, so I should finish Plex. also when try to backwards, TV is not responding at black screen.
It is like to occured exception on smart phone app