
Mermaid Man and Barnacle Boy III / Squirrel Jokes - S2-E4
Other mistake: Squirrel Jokes: When SpongeBob looks in the mirror backstage after finishing his second act, the holes on his face are not reversed in the reflection (one of the holes also vanishes and reappears mid-shot). The second time his reflection is shown, they are reversed. (00:20:18)

Mermaid Man and Barnacle Boy III / Squirrel Jokes - S2-E4
Other mistake: Squirrel Jokes: At the end of SpongeBob's second act, as he tells the crowd, "Thank you, you've been a wonderful audience," he opens his eyes briefly, and they are coloured yellow instead of white as they should be. (00:20:14)

Mermaid Man and Barnacle Boy III / Squirrel Jokes - S2-E4
Other mistake: Squirrel Jokes: Near the end of SpongeBob's second act, he tells the crowd to give a big hand to Sandy, but to clap slowly, because she's a squirrel. Right as he says, "She's a squirrel," the holes on the bottom left of his face disappear mid-shot, then reappear. (00:20:09)
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 ★