Nothing to worry about. Dropbox can only go by the geolocation data that is associated with your IP address. This will never be an exact match to your actual location. Usually, it's based off of whatever address was used whey your ISP registered their block of IP addresses. Best guess, your ISPs offices or data center are at or near that location.
I logged in to Dropbox today at 1:29 pm from San Diego, California. I got an e-mail from Dropbox that said: "We noticed you logged into Dropbox using Chrome on Windows 10 from Waipahu, HI, United States* at 01:29 PM GMT-07:00."
What gives? Is my account compromised by someone in Hawaii?