app to ipod problem

Hi-
when i made a certificate and a provisioning profile for my ipod it worked but i accidentaly deleted it. i requested a new certificate and made a new provisioning profile but it still doesn't work . whenever i run my app it says "

CodeSign "/Users/Documents/Apps/Math Game/build/Debug-iphoneos/Math Game.app"(1 error)

/Users/Documents/Apps/Math Game/build/Debug-iphoneos/Math Game.app: replacing invalid existing signature

/Users/Documents/Apps/Math Game/build/Debug-iphoneos/Math Game.app:
CSSMERR_TP_NOT_TRUSTED

Command/usr/bin/codesign failed with exit code 1

" how do i make it so i can test my app again?

 

on keychain access its says "This certificate was signed by an unknown authority.