Life is Strange 2 Ps4 problem?

I treated myself to Life Is Strange 2 yesterday, the edition that is on offer with all seasons but if I go to episodes in the menu, every episode except the 1st episode says "Buy"

Can someone explain this to me or what should I do now or should I maybe first play the 1 episode and then watch it?

Have you downloaded all other episodes yet?

Must download all the "buy" is like download, was also the same with me