How to complete this Zap app?

I have a Zap app that starts by leveraging a Mailchimp open trigger. Once a user opens an email in Mailchimp, I want to add a tag to the prospect’s record in my CRM app. The way I am going about this after the Mailchimp trigger is two action steps (would love only one but don’t know how to do it otherwise):

1. Find a Prospect via Email
2. Add a Tag to Prospect

I have been successful in retrieving the prospect’s data with Find a Prospect via Email. It finds the prospect from the Mailchimp email address and returns that data, as follows (subset of full dataset):

{
    "data": [
        {
            "type": "prospect",
            "id": 1436,
            "attributes": {
                "addedAt": null,
                "addressCity": null,
                "addressCountry": null,
                "addressState": null,
                "addressStreet": null,
                "addressStreet2": null,
                "addressZip": null,
                "angelListUrl": null,
                "availableAt": null,
                "callOptedOut": false,
                "callsOptStatus": null,
                "callsOptedAt": null,
                "campaignName": null,
                "clickCount": 0,
                "company": null,
                "companyFollowers": null,
                "companyFoundedAt": null,
                "companyIndustry": null,
                "companyLinkedIn": null,
                "companyLinkedInEmployees": null,
                "companyLocality": null,
                "companyNatural": null,
                "companySize": null,
                "companyType": null,
                "emails": [
                    "scott@.com"
                ],
                "tags": [
                    "California",
                    "C-Level",
                    "AZ",
                    "CIO",
                    "PST"
                ],
                "timeZone": null,
                "timeZoneIana": null,
                "timeZoneInferred": null,
                "title": null,
                "touchedAt": "2021-05-27T18:21:50.000Z",
                "trashedAt": null,
                "twitterUrl": null,
                "twitterUsername": null,
                "updatedAt": "2021-06-01T20:15:01.000Z",
                "voipPhones": [],
                "websiteUrl1": null,
                "websiteUrl2": null,
                "websiteUrl3": null,
                "workPhones": []
            }
        }
    ]
}

My biggest challenge right now is in getting the existing tags from the “Find a Prospect via Email” step to “Add a Tag to Prospect” because I cannot seem to extract the tags data and prepare it for a PATCH call.

Following is code I found from a similar question on here in my API call for Find a Prospect via Email” whereby I am trying to extract the tags data and prepare it for the next step:

return z.request(options)
  .then((response) => {
    response.throwForStatus();
    const results = response.json;

    let existTags = [];
    for (const item of results.tags) {
      existTags.push(item.tag)
    }

    // You can do any parsing you need for results here before returning them

    return [results];
});

But I continue to get an error similar to the following:

results.tags is not iterable
What happened (You are seeing this because you are an admin):
  Starting GET request to https://api.outreach.io/api/v2/prospects
  Received 200 code from https://api.outreach.io/api/v2/prospects?filter%5Bemails%5D=scott%40smeester.com after 182ms
  Received content "{"data":[{"type":"prospect","id":1436,"attributes":{"addedAt":null,"addressCity":null,"addressCountr"
  results.tags is not iterable

Can you help me write the correct code in “Find a Prospect via Email” so that I can compile that array or object that I will use in the next step, “Add a Tag to Prospect” to add the new tag to? 

Thank you in advance!!

Scott