Comparing an array in a Json response

I have this array set up from a previous GET response:

[85071929,85071930,85071979,85072029,85071899,85071900,85071901,85071902,85071903,85071904,85071905,85071906,85071907]
This is set as a collection variable I setted up from a previous call

These are a set of Ids and I want to compare with the debtor.id of this response because if an ID from that list is not found I want to use it for a POST request

[
    {
        "objid": 26425,
        "holdRef": "AP",
        "debtor": {
            "id": 485922
        }
    },
    {
        "objid": 26426,
        "holdRef": "AP",
        "debtor": {
            "id": 490503
        }
    }
]

This is what I tried:

var jsonData = pm.response.json();
var debtorIds = pm.collectionVariables.get('debtorIds');

for (var i = 0; i < jsonData.length; i++) {
    for (var j = 0; j < debtorIds.length; j++) {
        if ( !JSON.stringify(jsonData[i].debtor.id).includes(debtorIds[j])){
            pm.collectionVariables.set('debtorForPost', debtorIds[j])
            break;
        }
    }
}

but I’m getting this: “[”
image
not sure what I should do, thanks in advance for your help!

I solved my problem by parsing the Array variable as this
var debtorIds = JSON.parse(pm.collectionVariables.get(‘debtorIds’));