Hello @vojtechzikmund,
Thanks for writing to us.
There are several reasons affection your website loading speed for example
- Choose a better web hosting provider
- Reduce image sizes
- Minify JS and CSS files
- Use advanced caching mechanisms with a caching plugin
- Use a CDN
- Cleanup WordPress database etc.
Please have a look at our doc about website performance improvement https://theme.co/docs/how-to-improve-site-performance
You can also check out this article to learn more about how to speed up your WordPress site.
You may check our video doc as well

Performance Tips: Image Optimization

Performance Tips: Critical Path CSS

Performance Tips: Minifying HTML, CSS & JS

Performance Tips: Reducing Plugin Load
For the Google map, please make sure your theme, plugin, and WordPress are updated as per our version compatibility page. I would suggest you troubleshoot a few of the common issues.
If it doesn’t work, It would be best if you could copy your live website to your staging area. and send your details in a secure note so that we can investigate your setting without breaking your live site. Please provide the following details
- WordPress Login URL
- Admin level username and password
You can find the Secure Note button at the bottom of your posts
Thanks