[BO3]Why does my campaign progress only appears when I play on the PS4 and when I am on the PS5 only the Multiplayer progress?

Call Of Duty Black Ops 3 Why all of my campaign progress only appear when I play on the ps4 and on the ps5 it just isn’t there?

So in Black Ops 3, when I play the ps4 version in ps4 I have my whole progress but then when I play the ps4 version in the PS5 I have everything but the campaign I just don’t have it. Can anyone help me?