Sometimes a Windows update or other software might have made Registry changes to the size of spacing between the icons in a Fence.
This article will guide you to revert the issue.
press Windows+R to open Run window, type regedit and hit Enter.
Navigate to the following location:
HKEY_CURRENT_USER\Control Panel\Desktop\WindowMetrics
In the right panel, find out WindowMetrics. This is the horizontal spacing. Double click on IconSpacing to modify the value. Choose any value between -480 to -2730 where -480 represents the minimum spacing and -2780 represents the maximum spacing.:
The default value is: -1125