Los Angeles - Multiple tickets on single violation

What is the name of your state (only U.S. law)? CALIFORNIA

I was issued a parking ticket for violating street cleaning. Twenty minutes later I was issued an identical ticket by a different officer for the same violation, on top of the 1st violation.

I paid the first violation in full, but I can't find the rules on how long it has to be between tickets in Los Angeles. Everyone I talk to on the phone at the parking office says 24 hours, but my written appeal was denied and I'd like to cite code to get out of it. TIA

You can't cite a code because it doesn't exist. You were in violation the first time and you were in violation 20 minutes later.