Since you have 28033 finds on an "all finds"-search at geocaching.com (which combined with your 1388 would mean a total of 29421 caches) and the number of your total finds is correct at the geocaching.com statistics page title "Deepdiggingmole's Caching Chronology" I'd say this is an issue with geocaching.com were the total in the profile page doesn't match up with the total on the stats page. This is something that should be reported to Geocaching HQ.
If you happen to have logged a cache recently were you edited your log, for example posting a will attend on an event and editing it to an attended or editing a note on a challenge cache to a found, I would assume that cache is the likely issue. Either way Geocaching HQ should be able to correct it without knowing the cache, just write in on the appeals form.