curl --request PUT \
  --url https://api.topsort.com/public/v1/billing-service/campaign-billing-contact \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "billingContactId": "<string>",
  "campaignId": "3c90c3cc-0d44-4b50-8888-8dd25736052a"
}
'

{
  "detail": [
    {
      "loc": [
        "<string>"
      ],
      "msg": "<string>",
      "type": "<string>"
    }
  ]
}