The document should be in colour and clearly display your name, issue date, and residential address (non-P.O. Box address). Alternatively, you may use your ID (front and back) that has your address on it.
If your POA has been rejected, you will receive an email notification with the reason for the rejection. The most common reason for rejection is "uncleared documents", which means that either the uploaded image resolution is too low for us to review the details, or the image has been cropped.