Keep trying! I failed a few times.
I only had 2 games, so was fully expecting to allocate to a friend who has 3 games but is already sorted for a ticket. It hasn't asked me for another reference though! Not sure if the sales team will have cottoned this but I suspect it is because the "date" for booking history sales has passed.
Yep - the seat map. The greyed out block changed to without grey for the block in question. Kept refreshing every few mins.