Solved Edit a fence gate via clicked block

[Skeptified]

Hi, Im Skepp.
I've been trying to find how to make a fence gate open via a sign.

SCRIPT:

line 3 of the clicked block is "&b&lZone 1":
                    send "&b[Tap2Go] &eSuccessfully entered at &b&lZone 1&e!"
                    set {playertapinzone::%player%} to 1
                    set block at location at ~-1 ~-1 ~-1 of clicked block to air

The error is:

-1 of the clicked block is not a vector