PayPal Business - ORDER ID is missing from the form submission.

I've created a custom form to take payments, but once I hit the "purchase my tickets" button, I get a "ORDER ID is missing" message. See the link and attached screenshot below.

Hi there,

I've cloned your form, but can't seem to recreate the issue. I was able to send entries using both payment methods without a problem.

Try setting the Mode to "Test", revert it to "Live", then reconnect to PayPal. I've cleared your form's cache as a precaution.

Or, try to clone your form, see if the issue persists on the copy.

If you're still having trouble, you can try using PayPal Checkout.