Try Re-centering Camera [R Control, R Shift, Numpad 5].
If that doesn't work and you're view is still not “centered” when you press [Numpad 5] only, then you’ll need to restore your default snap view.
To do this, you need to delete the SnapViews.lua file from the config\view folder.
After deleting SnapViews.lua, make a copy of SnapViewsDefault.lua (also found in the same folder), and rename that copy SnapViews.lua.
Warning: If you have any saved snap views, this process will remove them as well.