In case your Verifone T650p becomes unresponsive and is frozen, you can follow the steps below to restart your terminal.
Note: Ensure that the power cable is securely connected to the terminal.
Power off the terminal for 10 seconds.
Power on the terminal
Retry the transactions
Check out this article if the problem persists.
Reach out to the Till Customer Support team by submitting a request ticket if the problem persists.