Pass JSON responds to local variable

I would like to pass the value from “Identifier” which is in my example below “e2d568b9-4d9b-4f5d-b716-11a9766ed6a5” to my local variable. So that I can use it in my next request as authorization password.
I have tried the following but the resutl does not store within collection Variable {{IdentifierToken}}

pm.collectionVariables.set(‘IdentifierToken’, pm.response.json().Identifier);

Is there a step by step guide that will explain this to me?
Thank you in advance.

"Value": {
    "Identifier": "e2d568b9-4d9b-4f5d-b716-11a9766ed6a5"
"TimeElapsed": 412


Found a solution to this;
set collection variable

Used the following line within test
pm.collectionVariables.set(“IdentifierToken”, pm.response.json().Value.Identifier);