APPLYING FOR KSAVISA IT WONT WORK

Hi, I’m applying for a Saudi eVisa from the UK for Umrah through the official KSA Visa website (ksavisa.sa).
I’ve completed all the sections and reached Step 7 – Application Review, but whenever I try to continue I get a red error message saying “Something went wrong” with no explanation.
I’ve checked my passport/personal details, security questions and terms & conditions. For my residency details I’ve put the UK, Manchester and my UK postcode. I’m staying at DoubleTree by Hilton Jabal Omar Makkah, so I’ve also entered the hotel details for my KSA address.
Has anyone had this exact error recently? If so, what fixed it? Also, what are UK applicants supposed to enter in the mandatory “P.O Box” field if they don’t have a PO Box?
Any help would be appreciated, especially from anyone who has successfully applied through the new KSA Visa website recently.