Request Error when creating a webhook subscription in Zapier

Site URL: https://stylebyilana.com

POST /1.0/webhook_subscriptions/ HTTP/1.1
Host: api.squarespace.com
Authorization: Bearer MYAPIKEY
User-Agent: ZapierIntegration
Content-Type: application/json
Content-Length: 106

{
  "endpointUrl" : "ZAPIERCATCHHOOKURL",
  "topics" : "order.create"
}

I'm using the above to try and initiate a webhook subscription for orders from my store to a Zapier function per the Commerce API documentation but continually receive the error "The value at JSON path 'topics' did not match the required type."

Any help would be appreciated