What this usually means
The reader can authorize a transaction while the machine-side vend command still fails.
What to check
Verify the exact controller or EPROM, cashless settings, MDB communication, and the reader harness for that machine.
Nayax Takes Payment but Will Not Vend
If the card payment succeeds but the machine does not vend, the reader and network may be fine. Check the vending controller, firmware, MDB setup, and harnessing.