I actually tried to send a feedback a few months ago, where I definitely didn't use the word "admin", still got the same message (I wasn't trying to talk to an admin directly or inquire a it being one, in any way). So I tried to send a feedback about why I couldn't send my feedback, and got the same message (because I guess I used the word "admin" to explain the situation). I tried a couple more times, don't remember if I got the feedback through or not
Classic has those issues with certain words. Some I don't even understand. Like I tried to do a smiley with a lot of mouths "

DDDDDD" and I get the "no cursing" message. Huh? I narrowed it down to "DDD". I don't know what that means of why it's offensive. There's also the annoying issue with ending a sentence (with a period), and typing a new sentence that begins with a word that starts with "com", "org", "net", etc.
Ah the annoyances of Classic's filter system..