I caught a suikune In mysterious island while having the water bell inside my bag and not it’s stuck

[Rascalisme]

Hello, I was doing a quest and at that time i got the water bell to catch suikune.. but I also got a mysterious ticket and caught suikune on birth island.. not I can’t exchange the water bell for any other bell or cant remove it from my bag pack.. what should I do? Cant I exchange it and catch a different dog?