Hi, it looks like a plugin is conflicting or possibly overriding parts of the theme.
The first thing to do is deactivate your active plugins one-at-a-time to see which plugin (if any) is causing the issue.
It is a process of elimination, so when we find the conflicting plugin we can then look into how to fix it.
Something is stopping the theme header from being rendered properly, and I can see a ‘Sumo’ login button in the header:
I am not familiar with this, is this powered by a WordPress plugin?
“I found the issue seems exoplanet doesn’t play well with wordpress free SSL certificate. Are there any updates or settings to remedy that?”
Totally unrelated to the theme. This is a WordPress issue. What usually causes the mixed content warning is when you have images which have been uploaded at at time before changing the site to https, so WordPress still continues to use the http path of these images.