I would say: too much help for nothing. We have nearly no information about the changes you made and what they are doing.So we can't reproduce your problem. My proposal for such cases: Go back to step one: load a clean JEM on a clean Joomla!
EDIT: And please can you specify/actualise all your information about your system: which Joomla! which JEM which additional template and additional templates, which changes you made.
Perhaps it could help if you give the link to your URL.
on JEM 2.3.0 stable in latest Joomla (3.9.16) Protostar php7.4.1