The site is not loading properly because of a 500 internal error on jQuery.

I've never seen that before.  I've seen it on PHP and stuff, but not on jQuery.

https://youtu.be/tsNovCXNZnY

Also some classes don't load like `btn-success` but that's ok I can just add them in, just letting you know in case it's important.

I'm having some weird row issue too.

https://youtu.be/VDZOv99eEhg

Again not important I can fix it, just reporting in case it's important.

The checkout issue is important it's stopping the checkout.

I'll raise a ticket with my host too.

I checked here and I have done all those items already: https://docs.j2commerce.com/j2commerce/getting-started/technical-requirements

Unmatched brackets in my override :)

Clue came from Akeeba Admin Tools and having it email me PHP error messages.  

RESULT.  Sorry to have bothered you.

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