Other mistake: The tenant board member tells George that Mr. Eldrige in apartment 8C has decided he wants the new apartment. However, the new apartment in question has a 3-digit number - 808 I believe. This indicates that the building would not have single digit numbers and letters (Such as 5E, 8C, etc.) as part of its numbering system.
Seinfeld (1990)
1 other mistake in season 8
Starring: Jason Alexander, Julia Louis-Dreyfus, Michael Richards, Jerry Seinfeld
Genres: Comedy
The Burning - S9-E16
Continuity mistake: At the beginning of the episode, when Puddy is farewelling Elaine on the street, he is standing on the sidewalk and leaning through the driver's window. The following shot when she pulls out quickly, you can see through the windows of the car that Puddy is nowhere to be seen.
Elaine: The thing about George is, he's an idiot.
The Robbery - S1-E2
Trivia: Michael Richards invented his patented Kramer entrance in this episode on accident. He missed his cue and thought he would make up for lost time.
More questions & answers from Seinfeld
Answer: The name is Delores. He shouts that name at the end of the episode. Then in a later episode, "The Foundation", he runs into her. And he repeatedly calls her Delores.