Relax, there's always a few kinks to work out after a delete if you have never done it before. You probably just unplugged that sensor by mistake when doing the delete, oops. I did that too with one of the sensors, can't remember which one.. Simple, plug it back in, clear the code.
No reason to worry about warranty at this point, that's moving backward. Its just a sensor. You deleted, now you are the warranty. If you weren't ready to accept that responsibility, you weren't ready to delete.
If you continue to have issues, call your tuner and Im sure they will take care of you. Good luck.