After a power cut, a router restart or a new internet provider, devices can get new network addresses and lose their connection to the Master iPad. Reconnect them in this order.
1. Start the Master first
Wait until the router is fully back online.
Restart the Master iPad and open Nomni POS.
Make sure every device is on the same Wi-Fi network as the Master (not a guest network or a 5G backup).
On each iPad, turn off Private Wi-Fi Address and Limit IP Address Tracking: Settings > Wi-Fi > tap the (i) next to your network.
2. Printers
Turn the printer off, unplug all cables from the back, wait 10 seconds, plug them back in and turn it on.
Print a self-test page. If it prints, the printer works.
On the POS, tap the printer icon, remove the old printer and add it again so it picks up its new address.
See Printer not printing? Step-by-step fix by printer model for your model.
3. Slave iPads
Force close and reopen Nomni POS on each Slave.
If a Slave won't reconnect, see Slave iPad not connecting to the Master: troubleshooting.
4. Kitchen display (KDS)
On the KDS, check the Master POS IP address. If it changed, enter the new one and save. See Nomni KDS not getting orders from the POS.
5. Card terminal
Make sure the terminal is on the same network, then reconnect it. See EFTPOS terminal not connecting or card payment failing on Nomni POS.
Stop it happening again
Ask your IT provider to give the Master iPad, printers and KDS fixed (reserved) IP addresses on the router. Then a restart won't change their addresses.
Still not fixed?
Contact Nomni Support only if the steps above did not work. Tell us your venue name, which device (Master or Slave), your Nomni POS version, what you tried, and a photo or screenshot of the screen. That lets us go straight to a fix.