Most table map problems happen when an iPad has fallen out of sync with Nomni Console. You can fix them from the POS.
A table has disappeared from the map
On the Master iPad, go to Settings > Sync.
Search for table and tap Sync Table from backend.
Run Master Sync.
Do the same on each Slave iPad.
Master and Slave show different or duplicate table maps
Nomni Console holds the real table map. If an iPad shows two maps or a different layout, run Master Sync on every POS. The duplicate disappears once all devices match Console.
Tables show as unknown, already assigned or greyed out
Check Held Orders first. The order may still be open on another device.
Force close Nomni POS on all iPads and reopen, starting with the Master.
Restart the Master iPad if it still happens.
Keep every iPad on the same version
Tables and held orders that vanish during service are often caused by iPads running different Nomni POS versions. Update all iPads to the latest version from the App Store after closing. Force close the app before updating. See How to update Nomni POS from the App Store.
Change the layout
To add, move or rename tables, see Creating Table Maps.
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 of the table map, and the time it happened. That lets us go straight to a fix.