curl --request POST \
  --url https://api.lemlist.com/api/campaigns/{campaignId}/leads/{email} \
  --header 'Authorization: Basic <encoded-value>' \
  --header 'Content-Type: application/json' \
  --data '{
  "firstName": "John",
  "lastName": "Doe",
  "companyName": "lemlist",
  "jobTitle": "Developer",
  "linkedinUrl": "https://www.linkedin.com/in/johndoe",
  "phone": "+33 123456789"
}'

{
  "campaignId": "cam_9NsHPnykWESTncCW8",
  "campaignName": "NEW TO DELETE",
  "firstName": "Bastien",
  "lastName": "Velitchkine",
  "companyName": "lemlist",
  "jobTitle": "GTM Engineer",
  "companyDomain": "bvelitchkine.com",
  "email": "support@lemlist.com",
  "_id": "lea_mizMsAEkRrJuhouYe",
  "isPaused": false,
  "contactId": "ctc_Rofmb6uNGyaPNZ2ni"
}