How do I reach Route 12 in Y?

Question

I was finding a site to find out how to get past this route, but what if I get a spoiler from the site? So I found this one, and I want to ask this question.

So, I can't pass Route 12 in Pokémon Y, a man is saying: "Hey, Trainer, not a good idea to leave the city when you still have pending matters with Korrina" And I don't know what to do next of this.

DON'T GIVE SPOILERS, I WANT TO KNOW HOW TO PASS.

Comments

Finish your pending matters with Korrina :s. Find her in the Tower of Mastery (upstairs).

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I can't go back, I just went back to her, and she only talks about a Lucario, stones, mega evolution, and it ends there, and it is never free for me to pass route 12.

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Did you ever actually beat the Gym?

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If so, there's a battle you need to do atop the Tower of Mastery. Did you do that?

Answer 1

Basically what Azelfeo said. Go to the Tower of Mastery, and do what Korrina requires of you. The Breeder should let you pass after that.

Source: Experience

Hope I helped!