When the record is in full edit mode:
De-select the sector that you want to remove from the record
And click the Save icon (
) when all changes have been applied to the record.
If you just want to edit the sector:
Hover over the sector box, the edit icon (pencil
) should appear in the top right hand corner.
Click the edit icon.
Un-tick the sector(s) you want to remove.
Click the Save icon at the bottom of the box (
).