As 6TDen has stated this is a DVLA problem NOT Insurance companies fault. If the reg number is not comming up on their data base then they cant issue insurance until it does. For example a Triumph 199cc (Tiger Cub)792XWH was registered by DVLA in Feb with V5c issued on 19 March 2026, its showing on DVLA web site but not on the AA car checker https://www.theaacarcheck.com/
Andy C look up you reg on the AA web site, I bet its not on which means that info has not gone over to 3 party and insurance compaines data bases yet. (Note the Triumph is not my bike, just one a found for an example)