Sounds to me like there could be a main door lock open or main board door / tray.
Power down unplug. Inspect around the locks you should see some wires going to the locks.
There COULD be a master optical lock on the door its referring to as well.
Look on the side of the machine, model and...
Dixie narco vending machine.
Freshly recharged and modified to be rechargeable in the future.
Can't find the keys but had some work done on the house had it moved out and moved back in just never used it again. Lock is popable
And probably 20 bucks to replace.
Bring a dolly and floor padding...
Fair warning.
If you decide to go token route make sure they are the same size as what ever its set to now.. Probably quarters in guessing?
If not same size you will have to change star in the Hooper and track and adjust counter at the end of the hopper.
Was this sudden?.
Was it powered down then powered up to this?
Where are you and the machine located?
I'm thinking possible cmos aka memory settings battery failure.
A new battery and a reset and it will probably come back to life and normal.