Posted on: June 06, 2018, 05:08:16 AM
Hello,
When you upgraded from 2.5 to 3.X did you completely reinstall the template with the current version? No 2.5 products work in 3.X, they must all be completely reinstalled with compatible versions. A 2.5 compared to 3.X has many differences, mostly css, which would cause an issue like you're describing.