Campbell, 18, joined the Cumbrians two weeks ago and made his debut for the League One club when he came on as a second half substitute in the home game against Coventry City.
But the youngster signed expecting to see more action than what he has been given.
A return to action for Lee Miller meant that opportunities to add to that tally have been limited and, following consultation between the clubs, it was felt that the best course of action for the player was to allow him to return to train with his parent club.