I have the same issue and like others here I was told to reset my phone to factory settings by customer support. I have found that the issue is that the phone somehow copies the grid layout of the cover screen and shows it on the main screen, thinking that the main screen is the cover screen (but without copying the background image). I too hope they find a fix for this that doesn't require me to reset my phone.
Yes... happens on my Fold 2 as well - sometimes when you open the phone you do not get a view that duplicates the first 2 cover screens (with small icons), but rather you get a full screen with large icons of just the first cover screen. It happens to me fairly often, at least a few times a day. Can we report this somewhere as a bug?