Mordent with Two Accidentals - How to Play?

[playerpiano]

How do you play this mordent with two accidentals? Thanks for any advice.
A link to the full score It is in measure 12.

[brogers70]

How do you play this mordent with two accidentals? Thanks for any advice.
A link to the full score It is in measure 12.

A little context would help, particularly the key signature and the next beat or two.

[lelle]

They mean that they are cancelling the double flat of the E in the bar before, and making it an E flat again. In other words, the upper note of the ornament is an E flat. The natural sign is unnecessary for that though, it's already understood by the flat accidental over the ornament, and even that E flat sign is unnecessary other than as a courtesy, as accidentals only last through the bar they apply to.

[playerpiano]

They mean that they are cancelling the double flat of the E in the bar before, and making it an E flat again. In other words, the upper note of the ornament is an E flat. The natural sign is unnecessary for that though, it's already understood by the flat accidental over the ornament, and even that E flat sign is unnecessary other than as a courtesy, as accidentals only last through the bar they apply to.

Thank you I understand now.