About 10 days ago, I submitted a revised manuscript based on the comments of Referee. But I just found out that I made a mistake in the newly added appendix. Now, the revised manuscript is under review, and I am not sure if the Referee is reading it or not.

So I want to know if it is appropriate to submit a new manuscript with the mistake corrected.

It is the first time I encountered this embarrassing situation. I should have been more careful.