1.NFC devices (mobile phones, tablets, etc. ) has not turned on the NFC function.
2. The 2.NFC tag may not be properly attached to the poster, or the tag may be damaged.
3. There may be something wrong with the NFC module of the mobile phone, which needs to be repaired or replaced.
You can try to solve the problem by following these steps:
1. Check whether the phone supports NFC function and make sure it is turned on.
2. Make sure that the label is correctly attached to the poster. If the label is damaged in any way, you need to make it again or get a new label.
3. If the phone can't read the tag, there may be something wrong with the NFC module of the phone. You can try to restart your phone, or send it to a service center for inspection and maintenance.
The above information is for reference only. If in doubt, please consult the mobile phone maintenance personnel or Air Force official website.