There's no Orff instruments any more???

Hello everyone,
I used to use Orff instruments to arrange scores for the Primary school where I work. One day, the last time I try to compose some ideas by using Musescore, I found out I could not choose Orff instruments at the beginning, when one is asked. Orff instruments seem to have disappeared from the window where they used to be.

May it be about the version I am using? How can get them back?

I would appreciate any kind of help.

Thank you very much in advance.