NFC Update Fails — Display Does Not Change
Likely Cause
The phone NFC antenna is not close enough to the tag, or NFC is disabled on the phone.
How to Fix
- 1Confirm NFC is enabled on your smartphone: Settings → NFC (or Settings → Connected Devices → NFC on Android; NFC is always enabled on iPhone with iOS 13+).
- 2Hold the phone flat against the tag surface — do not hold at an angle. The NFC antenna on most phones is in the top-third of the back panel.
- 3Move the phone slowly across the tag surface to find the NFC sweet spot — antenna position varies by phone model.
- 4Remove any thick phone case, wallet case, or metal plate between the phone and the tag — metal blocks NFC.
- 5Ensure the HPzenAi app is open and the Write to Tag screen is active before tapping the tag.
- 6Keep the phone still for 2–3 seconds after the initial tap — moving during the write operation interrupts the update.
Partial Update — Display Shows Garbled or Split Content
Likely Cause
The NFC connection was broken mid-update when the phone moved away from the tag before the write completed.
How to Fix
- 1Hold the phone firmly against the tag without moving until the update confirmation sound or vibration is received.
- 2Reduce the display content complexity — simpler layouts with less data transfer faster and are less susceptible to partial writes.
- 3Perform a full display refresh to clear the garbled content: HPzenAi app → Smart Tags → Refresh Display.
- 4If partial updates occur repeatedly, try with a different NFC-enabled phone to determine if the issue is phone-specific.
- 5Ensure the phone battery is above 20% — low battery reduces NFC transmission power and increases the risk of incomplete writes.
Display Showing Old Content After Update
Likely Cause
The update was queued but not yet written to the tag, or the tag received the update command but the display refresh did not complete.
How to Fix
- 1Confirm the HPzenAi app displayed an update confirmation message — if not, the write was not completed.
- 2Tap the tag again with the phone to retry the update — the app queues the latest content and resends on the next tap.
- 3For ETAG-STORE-1 shelf tags in high-throughput environments, allow 3–5 seconds between successive updates on the same tag.
- 4Perform a forced full refresh: HPzenAi app → Smart Tags → select tag → Force Refresh.
- 5Check that the tag is the correct one — if multiple tags are nearby, the app may have written to an adjacent tag.
Display Ghosting — Previous Content Faintly Visible
Likely Cause
E-Ink displays can retain a faint ghost of previous content after a partial refresh. A full refresh cycle clears ghosting completely.
How to Fix
- 1Always perform a full refresh when changing content significantly — partial refreshes are faster but can accumulate ghosting.
- 2From the HPzenAi app, select Smart Tags → select tag → Full Refresh to force a complete black-and-white cycle.
- 3If ghosting persists after one full refresh, perform two or three consecutive full refresh cycles.
- 4Avoid running more than 10 consecutive partial refreshes on the same tag without a full refresh in between.
- 5Ghosting is a cosmetic display effect only — it does not indicate a faulty tag or damage to the display.
Billboard Battery Low or Not Charging
Likely Cause
The HPZ-ST-BILLBOARD-DISPLAY-1 LiPo battery requires periodic recharging via USB-C — approximately every 6 months under normal use.
How to Fix
- 1Connect the billboard USB-C port to a 5V USB charger using the supplied or a compatible USB-C cable.
- 2The charge indicator LED on the billboard turns red during charging and green when fully charged.
- 3Allow 2–4 hours for a full charge from empty — do not disconnect until the LED turns green.
- 4If the billboard does not charge, try a different USB-C cable — the cable must support data and power, not power-only.
- 5Avoid fully discharging the LiPo battery — recharge when the app shows battery below 20%.
- 6If the battery does not hold charge after more than 12 months of use, contact support for a battery replacement.
Billboard NFC Update Range Too Short
Likely Cause
The billboard requires the phone NFC antenna to be within 10 cm of the tag's NFC antenna area, which is marked on the rear of the unit.
How to Fix
- 1Position the phone within 10 cm of the NFC antenna mark on the rear of the billboard.
- 2The billboard NFC antenna is located behind the display area — align the phone NFC antenna directly over this area.
- 3Ensure the billboard battery is charged above 20% — low battery reduces NFC response range.
- 4If mounted on a wall, temporarily remove the billboard for the update if the mounting position makes close phone approach difficult.
- 5Check that NFC is enabled on the phone and the HPzenAi app update screen is active before approaching the tag.
App Does Not Recognise the Tag on Tap
Likely Cause
The HPzenAi app NFC session has timed out, or the phone NFC subsystem needs to be restarted.
How to Fix
- 1Close and reopen the HPzenAi app, then navigate back to Smart Tags → Write to Tag before tapping the tag.
- 2Toggle NFC off and on in the phone settings to reset the NFC hardware: Settings → NFC → Off → On.
- 3Restart the smartphone if NFC issues persist — this clears any stuck NFC sessions from other apps.
- 4Confirm the tag is an HPzenAi Smart Tag — the app will not recognise third-party NFC tags.
- 5Ensure no other NFC app is running in the background — competing apps can intercept the NFC tap before HPzenAi receives it.
Tag Display Blank After Storage
Likely Cause
E-Ink displays retain their image without power for years under normal storage conditions. A blank display indicates the tag was stored with no content written.
How to Fix
- 1A blank (white) E-Ink display is normal for a new or factory-reset tag — simply write content using the HPzenAi app.
- 2If the display was previously showing content and is now blank, perform a full refresh to restore the display.
- 3Check that the tag was not exposed to extreme temperatures above 60°C or below −20°C during storage — this can damage E-Ink display cells.
- 4Inspect the tag for physical damage to the display area — cracks or pressure damage can cause blank areas.
- 5Contact support if the display remains blank after multiple write attempts and there is no physical damage visible.