make sure you do not use any add-ons or extensions in your browser that may conflict with your website.
Check for plugin conflict?:?Install the WP official?Health check plugin. Activate the troubleshooting mode. Then deactivate all of your plugins. If it fixes the issue, re-activate your plugins one by one, until you identify the plugin in conflict.
Child theme :?activate the parent theme if you use a child theme
Theme problem :?try to activate a WordPress default theme ( Twenty … )
Javascript :?make sure you did not insert custom javascript code ( like analytics, subscription popup… ), for example in a widget, that could break your site.