Is it spelled Addington? Is there a link to it on https://www.kingstonbrass.com/pages/sinks ?

That is a new one on me. And not a good one! I'm sorry this happened to you.

Kendrah, I think there must be at least one typo in "Addission." I tried several spelling variations and got nowhere. I'm not sure having the correct name would help, but it couldn't hurt.

Have you contacted the maker? I understand the warrantee issue, which is a major drag. But you might be able to find someone to advise you.

A websearch will take you to many sites where you can find out what could cause peeling of the surface on your sink. FWIW, Kingston says their sinks are ceramic, which is pretty durable, though not as durable as porcelain. The line you quoted above about the pristine finish is boilerplate; so far as I can tell, it's used in all their bathroom sink descriptions.

As it appears you did not abuse the surface, the answer is probably that the surface/coating was defective in the first place. A soft sponge and mild soap should not cause peeling. Has anyone but you ever cleaned the sink? Might they have used a more abrasive cleaner? (Even toothpaste can be abrasive, but it shouldn't cause what you show in the photos.)

If your DIY skills are up to it, you can likely repair it yourself. There are lots of tutorials online. Otherwise, I'm afraid you're looking at professional resurfacing.

The worst when something like this happens! Have you used vinegar or a cleaner with vinegar in it? I had an incident years ago where the homeowner cleaned with vinegar and it did this to the sink. Or do you use face cleaner, toothpastes or makeups that might have caused a chemical like reaction to the finish? I hope Kingston has an answer for you and it is a good one.

Wow - that looks like what happens when someone uses a "coating" on their bathtub/tile/sink. I am surprised that using natural soap and water would make the stain resistant coating to peel - especially after only three years.

Typically, a ceramic sink has a an enamel coating that is applied. The coating composed of powdered glass, quartz, clay, and feldspar, which melt during firing to create a non-porous, smooth, and glossy finish. I've never heard of this finish wearing off after such a short period - especially with the type of cleaning products that you use.

FYI - there are epoxy coatings that work well if you want to try to fix it. My understanding is an Ekopel 2K Refinishing Kit works best for longevity. It is more time consuming process (= takes longer to cure) + is more expensive (although I think they have smaller kits just for sinks which are less than the tub/tile kits) vs. spraying a Rustoleum coating on it - but it lasts for a long time. I have a friend who used it to refinish a vintage claw foot tub (probably around 4-5 years ago). She said that there are videos showing exactly how to prep and apply the coating.