error when submit token funcaptcha outlook

Why is this error 'cannot set attribute off null' occurring on line 73? When I inspect the element, the element with the ID 'verification-token' is inside an iframe with the aria-label 'verification-token.' I've also made sure that the frame is switched at line 67, and the element with the ID 'app' is only present within the frame element with the aria-label 'verification-token'. https://rentry.co/funcaptchatoken/raw