Checkout error: Failed to execute 'postMessage' on 'DOMWindow': The target origin provided ('')

Hi, so I get the title’s error when I’m in the checkout section and I try to add a coupon, the normal behavior is that when entering an invalid coupon it shows me a small modal with the message: “invalid coupon”, but I don’t get it and I think it has to do with this error, besides the array of messages of the orderForm object is always empty.

what could the problem be ?