There was an issue with our internal API, some connected distributors experienced intermittent problems with transaction processing between 2021-06-17 14:45:00 BST and 2021-06-17 16:15 BST. This issue mostly affected products in Passport ticketing system.
We have identified the cause to be regression introduced by a change in Core platform. Once identified, we promptly reverted the changes. All systems are operating normally once the changes were made.