combine specific mpeg-dash segments (ex int.mp4 + seg_1.m4s +seg_3.m4s) into one single mp4 file

Question

I am working one video transcoding in FFmpeg and MP4Box. Currently I am trying to combine/merge/concatenate specific MPEG-DASH video segments(m4s ex:int.mp4, seg_1.m4s, seg2,m4s,sge5.m4s) into one mp4 file.

This the example of what I am trying to do.

I have followed this thread ("Combine MPEG-DASH segments (ex, init.mp4 + segments.m4s) back to a full source.mp4?") but there is a problem while combining the specific m4s segments, while doing that it frames feazed in after seg2 and in seg5 it played again.

Reference: FFmpeg example