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.
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.
New Fish in Town/Big Sister Sam - S8-E10
Audio problem: In "New Fish in Town", Squidward pops out of his door and says "the bassoon." When he says it, the words are heard, but his mouth movements are delayed.
Banned in Bikini Bottom/Stanley S. SquarePants - S5-E20
Continuity mistake: In Stanley S. Squarepants, when Squidward moves out of the house with all his bags he doesn't shut the door, but when the shot zooms out, it's shut.
Continuity mistake: In "Once Bitten", Mr. Krabs is holding a key, about to unlock the doors to the Krusty Krab, when a customer stops him. Two shots later, the key is missing from his hands.
Krusty Towers/Mrs. Puff, You're Fired - S4-E9
Continuity mistake: When the rocks fall out of Patrick's suitcase, the rocks change number and position between the 3 shots.
Continuity mistake: When SpongeBob scrambles into the Krusty Krab to tell Mr. Krabs the "good news", the doors swing wildly inward. When the two return outside and see the Flabby Patty, the doors have varied from being open inward, to being open outward.
Atlantis SquarePantis - S5-E12
Continuity mistake: When Patchy finds Encino to have shrank, he hits his peg leg against his foot. When Encino is being turned back into normal, he is wearing shoes on both feet.
Atlantis SquarePantis - S5-E12
Continuity mistake: When Plankton is placed in a jar, there is a sign that says "No Flash Photography" above him. In the next shot, this sign disappears.
A Flea in Her Dome / The Donut of Shame / The Krusty Plate - S5-E11
Continuity mistake: In "A Flea in Her Dome", Patrick asks Spongebob to get on Sandy's shoulders. Then, he climbs onto Spongebob's shoulders. In the next shot, they are suddenly next to Sandy's tree.
A Flea in Her Dome / The Donut of Shame / The Krusty Plate - S5-E11
Continuity mistake: In "A Flea in Her Dome", Patrick gets bitten by a flea and his chest is covered in bites. He takes out a pencil and connects some of the dots to make a horse. A few shots later, the horse and the bites disappear.
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)
Continuity mistake: In "Sleepy Time", Spongebob is driving a car in his dream. When he starts to drive faster, he sticks his tongue out on his left cheek. When he makes a left turn in the next shot, it's sticking out on the right cheek.
Spongicus/Suction Cup Symphony - S6-E3
Continuity mistake: In "Spongicus" when Mr. Krabs and SpongeBob are outside looking at the "Chum Coliseum" and Mr. Krabs says "it's very suspicious" the tables inside the Krusty Krab are missing.
Jellyfishing / Plankton! - S1-E3
Continuity mistake: Plankton! When SpongeBob and Plankton are talking at night Plankton gives SpongeBob a golden spatula. When Plankton says he wants a Krabby Patty for his birthday SpongeBob drops it. Then when SpongeBob walks away, the spatula is nowhere to be seen.
Skill Crane/Good Neighbors - S4-E4
Continuity mistake: During "Good Neighbors" Squidward is sitting on his couch trying to enjoy his afternoon. SpongeBob and Patrick pop up behind him. In the next shot. Instead of Squidward sitting on his couch with Bob and Pat behind him, they are standing in the middle of the kitchen.
Help Wanted / Reef Blowers / Tea at the Treedome - S1-E2
Continuity mistake: In "Tea at the Treedome", in one shot, Spongebob's pants are inflated, and in the next shot they're not.
Buried in Time/Shellback Shenanigans - S8-E5
Continuity mistake: The authentic plate that SpongeBob accidentally drops in the time capsule and breaks repairs itself when it is seen inside the capsule after being buried.
Money Talks / SpongeBob vs. The Patty Gadget / Slimy Dancing - S5-E10
Audio problem: In "Slimy Dancing" in the scene where Squidward and Spongebob perform their act, we first see Squidward making Spongebob spin around. There's a shot where it shows Squidward inside Spongebob. The curtain in the background in the shot remains still, even though you can hear spinning.
Karen 2.0/InSPONGEiac - S8-E28
Continuity mistake: Squidward's house is missing in the shot that shows SpongeBob running from his house to Patrick's house.
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 ★