Rolex Claims Copied Serial Number - Advice?

[Joseph1260]

I purchased a Submariner Date (16610) in 1991. Came with box, tags, etc.
Has been on my wrist every day for the last 30 years, including dozens of dive trips all over world. Serviced once in 1998 by an independent watchmaker. Has worked flawlessly. Started to run slightly slower over the last 3 months.

Took it to Rolex Service Center this week - stunned when they told me, according to their records, the serial number on my watch had been "copied" and did not match the model of watch that I had. They refused to service it. Would not come out and say it but the inference is it was a counterfeit watch.

I then took it to an independent Rolex-trained watchmaker (40 years experience). He inspected the engraving on the serial number, the watch, and opened the case to look at the movement. Watchmaker says it's absolutely genuine Rolex watch.

I've asked Rolex to double check the serial number and provide any details they can. Rolex replied that I had purchased the watch (30 years ago) from a non-authorized jeweler (who is no longer in business) and basically there was nothing more that "they were at liberty" to tell me.

I agree w/ the independent watchmaker who said there is no way this watch would have performed for the last 30 years if it was a counterfeit. I don't want to sell the watch, only to resolve this serial number issue one way or the other. The serial number on the watch matches the serial number on the tag and paperwork I was given when I bought the watch.

Has anyone ever heard of a situation like this? Is there a possibility of a recording/clerical error by Rolex in their records? Watch was purchased for a very special personal occasion and has a great deal of sentimental value.

Any insight appreciated, thank you!