Your theme and other components of your site are breaking your site. I cannot go into depth in this forum.
You need to do some troubleshooting , see this docs page.
If all else fails and you cannot manage and need more information you can request a paid support ticket but the developer cannot and , will not, fix your theme or other plugins, he will point you in the right direction. You cannot just “swap over” to SSL without having experience in the technical complexities associated with such endeavors, I hope had at least backed up the entire set before attempting this type of change.