NYC got a ticket for having EXPIRED registration sticker not matching plate

Location: NYC/Connecticut

I recently got a ticket on my Connecticut-plate car for displaying an partially removed, expired registration sticker on the windshield. I moved from NY to CT in this past year, and as you may know CT does not do windshield sticker registration. I have changed my license plate and the registration to CT, but the sticker was for my previous NY license plate.

I did not remove the sticker completely because I thought as it is expired and not a CT registration, it would not work as a legal identification for my vehicle. I brought the car to NYC over a weekend, and got fined for standing a vehicle with registration not matching license plate. Are there any grounds for appeal? What should I do?