About 5 days ago I started having this problem, the Render setting menu tabs are disappearing
Looks like 3ds Max is messing with you. The first thing that comes to my mind is resetting the ENU folder, however it’s a bit “nuke it from orbit” approach. May be worth checking though…
https://knowledge.autodesk.com/support/3ds-max/learn-explore/caas/sfdcarticles/sfdcarticles/Resetting-3ds-Max-3ds-Max-Design.html
Thanks 
Did it help?
I changed it to 3ds max 2019 and the problem was solved