I was also frustrated 😤 during the time I applied for verification before.. I sent messages to support many times coz I wonder why its always error and coul even see the button for uploading photos until I asked someone's help and he told me to click desktop site coz I'm using phone. and that's it I able to submit successfully and get verified. If u are using phone try to use desktop site so u can see all clearly..
I also had the same issue for a whole day but while using desktop, I was able to compete verification pretty fast months ago. It may not even be the platform with which you are using to access and upload the documents and it could be anything.
Support on the other hand is a bit bad so you may not get quality response, all you have to do in this case is to keep trying and make sure you cross check what you are uploading.
I guess in my own case, I changed my document from drivers license to International Passport and it got accepted. Not sure if it was the desktop or the change of document that aided the verification, but what is important is to get it accepted.