SABA LMS not reading complete

Ah, you're using Cornerstone. The course not completing issue is one that plagued me too, and in some cases, I could never figure out what was causing it -- I just force-completed the course for the affected users. However here, I suspect it's user error. If the user closes the window when the course is done instead of clicking Exit, then the course will not register as completed. Have you asked the affected users to take the course again and then make sure to click Exit when they are done? 

I've also seen pop-up-blockers being on and browser extensions (like uBlock) interfere with progress, so check those too.  

If none of those work, then it may be network connectivity. For some reason, Cornerstone seems particularly affected by network dropouts and slow connections; you can ask the affected users to take the course during times of low network usage.

Hope this helps.