Pearson Vue terminated the exam without violation

I took a exam on today but pearson revoked my exam on the middle of the exam. Exam: SAA-C02 - AWS Certified Solutions Architect - Associate - English (ENU) Date: Monday, March 21, 2022 Time: 10:30 AM Japan Standard Time

The supervisor told me in a chat during the exam that my face was off-camera and it is rule violation. Concentrating on the problem, I thought i cloud do. So since then, I've been consciously making sure that my face is projected on the screen. But after that, the exam supervisor revoked my exam, saying I had violated the rules. Sincierely, I didn't do anything wrong, so I wanted to chat and hear the reason, but I wasn't given that chance. It's been a lot of hard work in the last few days and I'm very upset with this system and the supervisor for taking away the opportunity to prove this hard work.

I'd love to hear exactly what I did wrong. Or, if the process for canceling the exam is wrong, I hope you give me a chance to take the exam right away.