Just as an update; I have been in contact with Barclays and initially they said that it was probably a fault at the QuickFile end. I let them know that I’ve been in discussions with this side and it seems okay.
I’ve continued to give Barclays more information and it has now been escalated and being investigated. No time frame given but if I get any more updates I’ll let you know!
UPDATE: Barclays have finally got back to me to let me know that the Open Banking is only for Personal Current Accounts at the moment as a sort of trial… and there is currently no time frame for when Business Accounts will be able to use Open Banking. So basically it’s not possible at the moment - not useful at all!