Maybe wipe the fretboard with lem-oil.
That only works on unfinished fingerboards.
Yes I know what you mean, lem-oil would actually penetrate and soak into the pause of untreated fingerboards, I dislike playing with a dry untreated fingerboard.
However even though lem-oil will not solve the problem in this case it is still very good to use on treated fingerboards if use sparingly. It may in the long term help prevent any cracking or crazing of the treated fingerboard finish