Reply To: Invoice link to online payment after its been approved?

The submit fine for me, but you have a jquery incompatibility that results in no datepicker appearing. Maybe this error makes the forms javascript unusable in your browser. I think it comes from loading jquery ui from google instead of using the correct way to declare that. And then your theme loads it again in a third different version, but wordpress has jquery included so there’s no need for that.
All these jquery and jquery ui versions don’t work at the same time with each other…
Regards