How can I turn off the setting that allows a yellow underline on auto-corrected words in the notes app?

I use the notes app regularly, but every time I misspell a word and/or a word is autocorrected there is a yellow underline beneath the now-correct word. This would be fine if it went away, but it remains even when the word itself is deleted. I could delete everything in the note, and the yellow line would remain. ‘Undo’ doesn’t even fix it. I really can’t stand it, and hope there is a solution to this silly problem.

thank you for any assistance.