I'd send it in to the Citizen service center in Torrance, California and have them take a look at it. I had an Eco-Drive world time perpetual calendar go all wonky like yours did a couple months ago. It was a refurb so no warranty, I only had about $120 into it so I wasn't hoping for much. After I had sent it in and a couple weeks went by, I called up the customer service line and asked what needed to be done. They went ahead and replaced the movement and were boxing it up to send back to me, so that was cool.
That said, I've also paid for service, which I thought was reasonable as well. I had a pretty banged up Eco-Drive perpetual calendar that functioned fine, but the case, bezel and crystal were so hammered I didn't like wearing it. They ended up replacing the titanium casing and crystal completely, function tested everything, and did a waterproof testing on it before sending it back, that was about $200 all told.