Mitto integration - Request failed with status code 400

I have setup the SMS MFA integration for Mitto, followed the steps written in the guide but when we get the enrollment screen we get the following error message “Guardian - Error on send-phone-message-hook: Request failed with status code 400” can anybody help on this? I can also provide the raw log from Auth0 if needed.
Here is the Action Details

  "action_name": "Mitto v2",
  "response": {
    "error": {
      "message": "Request failed with status code 400",
      "name": "Error",
      "stack": "Error: Request failed with status code 400\n    at createError (/data/layers/layers-G_fj/G_fjn5c-Q5imlLZLZS2UFFFB0iAxiklmjGlg2xPDfAg/node_modules/axios/lib/core/createError.js:16:15)\n    at settle (/data/layers/layers-G_fj/G_fjn5c-Q5imlLZLZS2UFFFB0iAxiklmjGlg2xPDfAg/node_modules/axios/lib/core/settle.js:17:12)\n    at IncomingMessage.handleStreamEnd (/data/layers/layers-G_fj/G_fjn5c-Q5imlLZLZS2UFFFB0iAxiklmjGlg2xPDfAg/node_modules/axios/lib/adapters/http.js:260:11)\n    at IncomingMessage.emit (events.js:326:22)\n    at IncomingMessage.EventEmitter.emit (domain.js:506:15)\n    at endReadableNT (_stream_readable.js:1241:12)\n    at processTicksAndRejections (internal/process/task_queues.js:84:21)"
    "stats": {
      "total_request_duration_ms": 182,
      "total_runtime_execution_duration_ms": 180,
      "runtime_processing_duration_ms": 4,
      "action_duration_ms": 176,
      "boot_duration_ms": 4,
      "network_duration_ms": 2
  "error": {
    "id": "invalid_argument",
    "msg": "Invalid Argument"
  "started_at": "2024-04-09T07:32:28.618784432Z",
  "ended_at": "2024-04-09T07:32:28.801739141Z"