curl --request DELETE \
  --url https://our-secret-api-url.com/tokens \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --header 'X-API-KEY: <x-api-key>' \
  --data '
{
  "fcmToken": "<string>"
}
'

{
  "message": "<string>"
}