Randomly throughout my piece, the Play feature is playing notes that are not there, is there a way to fix this?

For example, in one measure the Bass part is a Whole Note, yet when I play the song, it plays two notes, which while it's not written wrong, it will throw off all the parts once I add them. This whole note is just one example of this problem, it's just the most egregious. Can someone please help me with this, I've already tried deleting the note and putting it back, and deleting the measure and making a new one, I have no idea what is causing this. Thank you!