To use the test request feature you need a valid leadThing.dev API key, please sign in to get one.
{"url":"https://leadthing.dev/api/acumbamail","method":"POST","headers":{"apiKey":"Sign in to get your LEADTHING.DEV API key","content-type":"application/json"},"body":{
firstname:"John",
lastname:"Smith",
email:"john.smith@example.com",
subscriptionMode:"DOUBLE_OPT_IN",
listId:"1234"}}