The most likely reasons for this to fail are:
- you might not be aligning the NFC reader on your phone with the passport chip; or
- your passport chip might be malfunctioning.
To successfully read the passport chip, while your phone is on the back of your closed passport, try changing the position of your phone slightly and wait a moment as some phones may have difficulty connecting to the chip.
If you continue to struggle, you can simply skip the chip read and just scan or take a photo of your passport.