Summer Job - S7-E18
Continuity mistake: Mrs. Puff hands Spongebob the order for a Krabby Patty. In the next shot, he is not holding the order, nor is it on the floor.
Back to the Past/The Bad Guy Club for Villains - S7-E16
Continuity mistake: The Quickster was a member of the I.J.L.S.A in Mermaid Man and Barnacle Boy V. But in this episode, there isn't The Quickster in the I.J.L.S.A, but instead the Pi-Right Ponderer.
Summer Job - S7-E18
Continuity mistake: Mrs. Puff didn't know that SpongeBob works at the Krusty Krab, when she already found out in 3-18 "Krusty Love." Even stranger thing, Mr. Krabs and Mrs. Puff have no idea who each other are, but they also already met in that episode.
Chosen answer: You need to provide a little bit more information to be able to answer a question like this. In what region is it not being shown? I see it being replayed here in Australia fairly frequently. As for a general reason, there does not appear to be any for why it specifically might have been taken off the air in any country or region. Like any show certain episodes can sometimes not be replayed for long periods for unknown reasons.
Lummie ★