Marmaris
When the order is placed by the customer, if the delivery guy is automatically receiving the order, that means, the store has enabled the "Auto-accept" order setting.
In this case, there is no accept/cancel button for the store owner dashboard.
It would be helpful if you can create a screen recording or a video with your phone of the process to recreate the issue on our end. As it's working completely fine on our end as of now.
Make sure there is no customization done on any of the code and it is purely 2.9.1.