Just realised I cited a source in my EE that doesn't exist in my bibliography

Like I have a reference for what I am saying but when I checked the bibliography there isn't this source ANYWHERE. I probably deleted while reorganising my sources. I checked all my other citations and they are legit but what about this one? Is this an academic dishonesty problem? Are they going to reject my EE?? I

It's already submitted so I can't change it.