PS4 does not see my request?

Fr
4

So I have a switch and a friend plays on ps4 and we wanted to play fortnite but he does not get a friend request. I can, however, send one. What's wrong?

ob

You can't play with each other because you both have different consoles.

Fr

I have already played with friends who have ne ps4. That works already

Ru

Fortnite is cross-platform.

Pa

Can he send you one?