I am a Singaporean, and I have encountered the same issue with verification. I initially attempted to verify my Identification Card using the webcam and later switched to uploading a scanned image of my Identification Card more than 10 times, but all attempts failed.
I reached out to support, and they provided a lot of useless advice. First they asked me not to cover my ID number, which I found ridiculous because the website clearly advises me to cover it. Then, support suggested not using any software to edit my ID number and recommended covering it with white tape instead. I tried it, but it failed. They also suggested using black tape, but none of these solutions worked. They also advised me not to cover the card with my fingers, which seemed strange to me because I had already switched to uploading scanned images when seeking their assistance.
I believe that they are simply reading answers from the FAQ sheet and have no idea about the actual issue. I also tried changing my profile photo, but it didn't help at all. Currently, support has been ignoring me for days on the live chat because I requested them to escalate the issue to the specialist team and likely that no one on the team is available to respone due to the approaching Christmas holiday.
If any other Singaporeans have experienced a similar issue with IC verification on Airbnb, please kindly advise me on the steps I should take to resolve this problem. Thank you.