There are 2 primary causes for the printer not responding:
First up is Bluetooth power saving, which will shutdown the connection to the printer.
Second is a reset of the PDA software, this can sometimes be when the server is restarted – although this is less common.
Follow through the below steps to get back up and running.
1. Open up your Zii Assist PDA software, and select Setup from the drop-menu at the top right of the screen – usually shows as 3 vertical dots.
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2. Once in the Zii Assist Setup menu, you should see something similar to the below photo.
Select the option Connect Printer ME31-6A1A
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3. You should be shown a pop-up display with the printer – tap the printer.
If the printer does not show up, make sure it is powered on and charged up.
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4. Press the orange Save button.
Your printer should now be connected and working – you can now try printing a ticket.