I’ve gone back and forth from the beach for around 5 days since completion, is there a certain time it has to be or a certain day?
I don't remember the specifics, but in the wiki, under "special order quests", says:
Quests are set objectives that provide rewards when completed. They're kept track of in the quest journal, which can be brought up by clicking the exclamation point icon at the bottom of the date/time display in the upper right of the screen, or by using the hotkey F. Current progress on a quest...
stardewvalleywiki.com
Rewards: 3000g, Quality Bobber recipe, cutscene at the beach. Under Quality Bobber, it says: "It can be
crafted from a recipe received from
Willy in the cutscene that follows the completion of the
"Juicy Bugs Wanted!" Special Order."
So, unless you trigger the cutscene, you cannot gain the recipe itself. You have to see willy fishing, next to a disgusting pink pile of meat, in a cutscene!