Just to get this straight was it a demo bike or your own ?
If its yours did they repair it ? NO ITS A DEMO !
If so its your word against there’s…but if I were you id give Citizens Advice a ring first and get there stance on it.
It wasnt fit for purpose !
Just imagine if that had happened on the road !
Be strong speak with the owner/manager
(I work in the trade and have done so for 12 years)