Kappas delivery glitch - impossible to get all the deliveries achievement

[aya !?]

(Spoilers)

I will try to explain exactly what happened to me:
After beating the game, the blue seed item appeared in the last slot of the deliveries inventory - which looking now, i don't think it was supposed to do that. But anyway, i went exploring and got all the collectibles, so the last thing to do was to bring the kappas to the heart of the mountain. The problem is, the aquariums were actually invisible. I could see the sparkles but there was nothing there where they were supposed to be.

So i restarted the game and now the aquariums were visible, then i got all the kappas and went to the heart of the mountain... but when i got there, all the kappas were already on the water, and the blue seed was on the floor - i had the 3 kappas with me, so they duplicated somehow. I gave the seed to Vanny, but never actually delivered the kappas to the lake. And now i'm stuck and would have to play the entire game again to get all the deliveries - which btw i would, bc this game is so nice, just really upset about this glitch right at the end...

[Raul5c]

I have the same bug :(

[fffirey]

Something similar for me. Turned in 1/3 before beating the game. Just beat it and went back to complete all the things. I collected the remaining 2/3, but can't turn them in - no NPC in the cavern, and all three are already in the water.

[NEXGENEEZY]

same bug happening here

[Chibig]

Hi all! We'll be checking this as soon as possible, sorry for the bothering. Thank you for sharing it here and playing the game!

[Day]

Same here, although i delivered 3/3 it says "2/3", hope they can fix it soon :(

[AbyssQueen69]

Same issue; beat the game and had to look up a guide on what I was missing and three kappas but the heart of the mountain turned into a seed and left and I delivered the seed already