Immortal Pet leveled to 20, not counting for kingdom prestige

Platform, device version and operating system: Xbox Series X

Screenshot or image: Don’t have one

What you were expecting to happen, and what actually happened:
I leveled up Immortal Khaomani’s pet, Khaomani’s Engel to level 20, but it is not counting as a level 20 pet in Bright Forest.

How often does this happen? When did it begin:

Just once, I had 5 of 6 level 20 pets before leveling this pet to 20, and still have 5 of 6 after. It did not advance the task.

Steps to make it happen

Can’t do it again, only can hit level 20 once (max).

Have you tried opening a gold chest? In case it’s like the shiny bug and the trigger is broken.