In the episode titled " Summer Job " (Season 7, Episode 28 in some broadcast orders, or 136b), Mrs. Puff is forced to work a summer job at the Krusty Krab after crashing her boat into the restaurant while trying to escape SpongeBob.
: Mrs. Puff attempts to flee from SpongeBob, but her boat crashes through the front of the Krusty Krab. [S7E28] summer job
This note ironically serves as the evidence that lands Mrs. Puff in jail once again, as she had destroyed it earlier, and its "reappearance" leads to her being arrested for littering. In the episode titled " Summer Job "