Winter Contingency not working

Why did the challenge stop at level 5?
It never moved from there and I don’t have the banner to complete it.

Do I have to wait or something?

Each event pass tier is time-gated. You can get one tier per day by playing a match, it’s not linked to challenges.

Play a game a day for 10 different days and you should complete it all.

Consider it a bit like an advent calendar, I think that was their intention, although after the fracture event this has really confused a lot of people.