When do I unlock a new broadcast tower mission

So, I just did the elite four and after doing the kyurem quest I decided to do the broadcast tower missions. I just did the first one and I was wondering if there a spesific thing to do to unlock the next mission.

You should be able to unlock the mission just by running around.

They’re based on story progress and the amount of badges you have. If you meet a new requirement, walk around and you will get a call.