Is it a forever stamp? If not, add enough stamps to make at least 50 cents and you are good to go. I did this sometime ago with no problem.
Stamps never expire ,you just have to add the extra money.
A few months ago, I came across whole sheets of 1 cent and 3 cent stamps from heaven knows how long ago. They're the lick-and-stick type; probably the glue is no good.