No arrangement is final. She can experiment with using other chords in the key the song is in, and depending where this occurs a major chord may work quite well. I did have Bminor's made for my harps but they were cut wrong, so for years I didn't have the use of them and made out fine just changing the arrangement. Especially if she is not playing solo, the alternate chord need not be an issue.

Also she can try experimenting around the chord buttons to play 2 chords at once, and she may get a compatible-sounding resulting chord that will work for her on an existing arrangement. It will be a thin sound in that spot, but may work.

Another work-around is to simply retune the whole harp so that playing it in Am-marked chords actually results in playing in Bm, etc., if that is the most commonly-played in key for your group. Her arrangements will need to be transposed to appear in the key that matches the chord names on the buttons she's using. (Using this example, of course that also means that she will not be able to conveniently play in Am.)

But it is true that people who play with autoharpers learn to respect the chords they DO have, especially when the person is newer to playing.

~Susan