can not delelte on Fortimanager the fortilink interface

[Kaplan]

Dear People,

I hope somebody can help me.
I try to delete the fortilink interface.

If I use the checkbox

Where fortilink is used

VDOM    Referrer Type        Field

global    system ntp             interface

All DHCP Server are deactiveted

I can not delete the fortilink interface

Can somebody explain a solution?
Thanx in advance

[Kaplan]

No not now. If there was something noticed, when you use "where  used", so it's not possible. In the past I have tried more then one time.