AMS is generating m3u8 file having less segments than total duration of video

I have few mp4 files of one hour. For few mp4 files m3u8 has few less segments than total video duration, While for other mp4 files it is working properly and generates proper m3u8 file.

For m3u8 which are having problem, when i hit .ts file in browser, which are not in m3u8 file but its within duration then actually it returns .ts file. So it seems AMS generates .ts files properly but somehow not added those into m3u8 file.

e.g. for segment duration 8 seconds, suppose m3u8 file has 379 .ts entries (which is 50.32). Now when i try to get .ts file upto 450 (a hour) it returns those files.

I tried to put mp4 files on two AMS server, and both have same problem.

What could be the problem?