Check the Layers menu (top-right, between Account and Layout).
Is everything set to be visible in that dropdown? Make sure the eye icon is visible like this:
If not, anything on that layer will be hidden in Scene view.
New GameObjects are put on the ‘Default’ layer when they are created.
didnt work for me eithre i have default and everything checked, i also have the box top left next to my objectbox checked in the inspector checked