When submitting spam email using the Email False Positive Submissions tool, you see the message, "This email is not classified as spam" even you submitted email which was detected as a spam by Email Security.cloud.
You want to know why email was detected as spam but the tools does not accept it for investigation.
Note that you confirmed the situation does not meet the article:
"This email is not classified as spam” when using the Email False Positive Submissions tool
https://knowledge.broadcom.com/external/article?legacyId=tech233678
The Email False Positive Submissions tool intermittently cannot accept email correctly.