How do I unroot my phone?

[lovatic96]

I have a Samsung Galaxy Core Prime from straight talk (SM-S820L). I tried to look for the stock ROM, but I can't find it. I also tried Universal Unroot. It says it's not rooted on Root Checker, but I still can't update it. Any advice on what to do now or where to find the stock ROM?

 

[anon(632115)]

There doesn't seem to be a stock ROM available. Try Smart Switch emergency firmware recovery. If that doesn't work, I'm out of ideas. AFAIK Straight Talk don't provide updates