I voted to reopen Finding address with coordinates? before realizing that it is in fact a duplicate of the question it's currently marked as a duplicate of.
Can I retract my reopen vote?
The ability to retract re-open votes is the subject of a feature request at Meta Stack Exchange - see Ability to retract reopen/delete votes.
It has been open for more than 5 years and appears not to have been implemented nor declined by the Stack Exchange developers.