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Continue to ChatMystery Box closes itself after being used once, only way to reopen it is to wait before transferring more Pokémon from Pokémon GO to Pokémon Let's Go https://pokemonblog.com/2018/10/10/mystery-box-closes-itself-after-being-used-once-only-way-to-reopen-it-is-to-wait-before-transferring-more-pokemon-from-pokemon-go-to-pokemon-lets-go/