Thanks for this reply, I am pretty sure the error is not from my side.
@Charles-Tim what is your Android/wallet version?
I read some comments in above link and some of them indicate that the problem is related to Android 10.
I tried it on Android 9 Wallet version 4.3.2 without problems.
Can you tell us more information, what device you are using and what version of Android?
Android 12, running the lastest update. I later tried it on my old device which I remembered I have exported th file before successfully, it did not also work, but I upgraded the device from Android 9 to android 10 immediately the phone Android 10 update was released.
Did you mes around with your smartphone, maybe installing some custom android rom, rooting phone and unlocking it?
No