Mobile:
Go to Assets tab
Select Asset with Sub Location to delete
Click arrow to right of Location
Under Sub Locations, click arrow to right of Sub Location to delete
Click 3 dots (...) next to EDIT in top right corner
Click Delete
Click Yes
Web:
Go to Locations tab
Select Location with Sub Location
Click arrow to right of Sub Location
Click 3 dots (⋮) next to Edit in top right corner
Click Delete
Click Confirm