This solved it..
After trying all options mentioned with no success this was the real solver for us.
Turn off Elastic search
Steps taken -----------------
1. Store Configuration
Stores > Configuration > Catalog > Catalog
Section > Catalog search
Item > Search Engine
Set to Use system default (MySQL) an Save
Step 2 Cash Management
System > Cash Management
Select the lines and choose Submit to refresh
Step 3 Load Category
All products are show as they should.
We will look into the real reason why Elastic search did have this problem.
It will be added to this forum later when we found it...
Thanks
