Icing not set

I made last night a neenish slice it has icing made with icing sugar, a little butter & water. I put it in a container with a lid after it had cooled but today it is kind of sticky. How can I get it to dry out I don't need it until Saturday. Help please.

Chef_denart, Mar 20, 3:54 am

Try leaving them out in the air. that might work.
Otherwise scrape off the icing and add more butter to the mix

Chef_rainrain1, Mar 20, 4:00 am

Thanks rainrain I will try that. Can't really scrape it off as its got the white icing under the chocolate one.

Chef_denart, Mar 20, 4:06 am

Of course, I had forgotten, so long since I made those,

Chef_rainrain1, Dec 11, 3:43 pm