curl --request POST \
  --url https://api.example.com/api/v2/{portalId}/auth/signin \
  --header 'Content-Type: application/json' \
  --data '
{
  "wallet": "<string>",
  "message": "<string>",
  "signature": "<string>"
}
'

{
  "accessToken": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwid2FsbGV0IjoiMHhmMzlmZDZlNTFhYWQ4OGY2ZjRjZTZhYjg4MjcyNzljZmZmYjkyMjY2IiwiaWF0IjoxNTE2MjM5MDIyfQ.-fu_kTkRsmXqWwwrmsSgb78S504bkkZXp_e92RaJTw0",
  "expiration": "2024-12-31T23:59:59.000Z"
}