Shuffleboarding/Professor Squidward - S6-E17
Other mistake: Shuffleboarding: When the jail explodes and all the fish fall to the ground, one fish hits the ground and then disappears mid-shot. (00:10:45)
Nature Pants / Opposite Day - S1-E9
Other mistake: When SpongeBob throws the fire extinguisher at the grill, the patties are shifted to the left and appear to be floating.
Continuity mistake: Rock Bottom: When the cardboard version of SpongeBob next to the candy machine is shown, it is frowning, but it turns into a smile mid-shot when it falls over. (00:18:48)
Jellyfishing / Plankton! - S1-E3
Continuity mistake: In "Jellyfishing", Patrick and Spongebob slide down two ropes and burn their hands on them. The two shots after they land show them trying to cool down their hands and in the shot after that, the ropes they had just slid down on have disappeared.
Help Wanted / Reef Blowers / Tea at the Treedome - S1-E2
Revealing mistake: In the shot where Spongebob says, "That little squirrel is in trouble, " half of his belt is missing.
Mermaid Man and Barnacle Boy IV / Doing Time - S3-E1
Other mistake: When the citizens pop out of Sponge Bob's holes near the end of Mermaid Man and Barnacle Boy 4, if you look closely, Sandy's head is gone except her eyes and nose.
Revealing mistake: After SpongeBob disguises himself as Patrick's rock and right before he sneezes his uvula clips through his bottom lip.
Continuity mistake: When Plankton is telling Karen, "There's a whale in the laboratory," he is jumping up and down with his arms in the air, but in the next shot, his arms are suddenly down at his side.
Continuity mistake: When SpongeBob accidentally reveals the location of the formula, Plankton drops the feather he is holding and lands in front of him. The feather remains on the floor, but when Pearl walks into the kitchen, the feather has suddenly vanished, and reappears in front of Plankton in the next shot.
Continuity mistake: When Mr. Krabs and SpongeBob are standing in front of the bomb after it lands but doesn't go off, the clock inside Mr. Krabs' office can be seen from the kitchen. The time on the clock is 5:00, but in the next shot, the time on the clock is suddenly 3:00. The bomb is then revealed to be a mechanical hand, and the time on the clock is now 5:00 again.
Patrick-Man!/Gary's New Toy - S9-E2
Continuity mistake: In "Patrick-Man", in the scene after Mrs. Puff gets arrested, the guy that SpongeBob serves the krabby patty to in the Krusty Krab is not wearing a T-shirt until the guy says "Lets hope Patrick Man doesn't confiscate this one," then he is seen wearing a white T-shirt. (00:08:00)
Help Wanted / Reef Blowers / Tea at the Treedome - S1-E2
Character mistake: In "Help Wanted", Stephen Hillenburg's name in the "Written By" section of the title card is incorrectly spelled as "Stephen Hilleburg."
The Krabby Patty That Ate Bikini Bottom/Bubble Buddy Returns - S8-E15
Continuity mistake: At the beginning of Bubble Buddy Returns, right after SpongeBob reads the letter from Bubble Buddy, Gary's swirl is blue and his spots are red.
The Secret Box / Band Geeks - S2-E14
Continuity mistake: When the band is marching through the streets, whilst Squidward is pressuring the flag twirlers to move faster, there are some fish drumming behind them. One is a blue fish wearing a yellow shirt seen standing on the left, and another is a brown fish wearing a red shirt seen standing on the right. When the flag twirlers behind to fly off the ground, those two fish have swapped places.
The Secret Box / Band Geeks - S2-E14
Continuity mistake: In Band Geeks during the Day Two scene, in the beginning you can see Pearl near the front, but in the distant shot that follows Pearl has moved further back. (00:04:20)
Other mistake: When SpongeBob has his picture taken, his tie is missing.
Born Again Krabs (aka A Penny Saved) / Safety Freak (aka I Had An Accident) - S3-E17
Revealing mistake: I Had An Accident: Almost every time the actor in the gorilla suit is on screen, he is transparent, with the background showing through him. (00:20:48)
Patrick SmartPants/SquidBob TentaclePants - S4-E8
Continuity mistake: Patrick SmartPants: When SpongeBob first looks at his scrapbook, the title on the cover reads, "MY FRIEND PATRICK." In the next shot, it now reads, "MY FRIEND Patrick," with "Patrick" no longer being in all capital letters. The words also change from blue to purple between shots. (00:07:51)
Other mistake: At the Krusty Krab, SpongeBob tells Squidward to write a letter. Patrick then tells SpongeBob that he ripped his paper, and SpongeBob's shoes lose their colour mid-shot. (00:06:45)
Sandy, SpongeBob and the Worm / Squid on Strike - S2-E18
Continuity mistake: Squid on Strike: The first time Squidward opens the door to his house, the door opens to the right. Later on, when he opens it again and sees Mr. Krabs, it now opens to the left. (00:09:03 - 00:09:40)
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 ★