Hi @scottpickavance,
Welcome to the Dyson Community!
This sounds like an unusual issue - the mechanism on a brand new machine may be a little stiffer to begin with, and need slightly more force than usual to disengage the bin. We’d soon expect this to relax with continued use.
If you continue to have issues after trying again (applying a firm, constant force to the release button), we'll need our Customer Care experts to take you through some further troubleshooting checks when you have your Dyson Cyclone V10 vacuum easily to hand. If a replacement part or a repair is needed, they’ll be able to discuss your options with you.
Please visit Dyson.com and click Support to get in touch with the right Dyson Customer Care team for your region.
We'll look forward to speaking with you!