2671291 - Number Range: Unable to delete intervals, deletion button is missing

You want to remove an existing interval from a Number Range object on SNUM transaction > Interval Editing (F7):

But ‘Insert Line’ and ‘Delete Line’ buttons are not offered:

 You were expecting output like this:

SAP NetWeaver

Insert Line, Delete Line, groups
SNUM, SNRO , KBA , BC-SRV-NUM , Number Range Management , Problem