A freaky glitch with Shiny sandwiches

Today, I was attempting to shiny hunt Tinkatink in the ruins close to Cortondo, and just after I did the Fairy sparkling sandwich, I noticed the regular spawns like Drowzee and Bronzor kept spawing, but little to no Tinkatinks. And I know for a fact that Tinkatink spawns in good numbers in that area because I attempted this very shiny hunt yesterday.

I reset the game and try again, and nope, no Tinkatinks. Then I fast travelled to Glaseado's Grasp to try with Frigibax (dragon sandwich) , and no Frigibax spawned, just the regulars like Bergmite and Cetoddle. I even turned my Switch off and on, and the sandwich still didn't work. Mind you, I have used these sandwiches (The ones with the hamburger) pretty successfully so far and this didn't happen until today (the game even said that the meal effects were on) . The only way I got to undo this glitch or whatever, was to shiny hunt in the Crater.

So far, this seems to have resolved the issue as I did a few shiny hunts again in the overworld (including the Tinkatink). Maybe it helped that I sort of "despawned" and " respawned" the whole map by going into the crater, but it was pretty darn freaky it happened out of nowhere. I was even fearing I broke the game and couldn't shiny hunt in that profile again.

Has anyone else had a similar experience with this sandwich glitch? If so, have you resolved it and how? It would really help to know other stories like mine.