Nostalrius Begins - Quality wow vanilla realm (1.12)

I want to leave my pet at the stable master so i can tame a new one and i bought a pet slot but when i try to drag the portrait there it wont stay there, and ill keep it with me no matter what. I tried to relog, to do it while the pet is summoned/dismissed and everything! The pet portrait has a yellow bright around it tho but i dont know what i means, its my first time rolling a hunter. please help

Your pet is summoned, alive and active when trying to stable him?
And you haven't put a pet in there in the past at all?

Try logging out, turning off all your mods, log back in.
If that doesn't work, try clearing WTF & WDB folders.

Did it spawn another pet when you put ur original pet in the stable?


Edit : If so try using this command.. /script PetAbandon()