Documentation Index
Fetch the complete documentation index at: https://developers.vfbulk.ie/llms.txt
Use this file to discover all available pages before exploring further.
Use this page to diagnose common authentication, campaign, Sender ID, and callback issues.
Authentication issues
| Symptom | Likely cause | Fix |
|---|
401 Unauthorized from the API | Missing, expired, or invalid access token | Request a new token and retry the API call. |
invalid_grant from the token endpoint | Incorrect username or password | Check the credentials supplied for the Bulk Text account. |
| Token expires during processing | Access tokens are short-lived | Re-authenticate before requests or retry once after 401. |
| Request is rejected by the token endpoint | Wrong content type or form body | Send application/x-www-form-urlencoded with grant_type=password and client_id=ismstoken. |
Campaign request issues
| Symptom | Likely cause | Fix |
|---|
415 Unsupported Media Type | Request is not JSON | Send campaign requests with Content-Type: application/json. |
| Message is not accepted | Missing required field | Include text, from, and at least one recipientInfo entry. |
| Some recipients are skipped | Invalid recipient numbers | Review the errors array and correct the affected msisdn values. |
| Account has no credits | Message processing returns a credit error | Add credit or contact bulktext.ie@vodafone.com. |
| Scheduled message does not send when expected | sendAt is not UTC or has the wrong format | Use UTC in yyyy-MM-ddTHH:mmZ format. |
Sender ID issues
| Symptom | Likely cause | Fix |
|---|
| Sender is not valid | from is not approved on the account | Call GET /api/v2/senderlist and use one of the returned values. |
| Irish recipients do not receive messages | International non-ComReg Sender ID used for Irish traffic | Use a Type 0 ComReg Sender ID or Type 2 numeric Sender ID. |
| New Sender ID is unavailable | Registration is not complete | Contact bulktext.ie@vodafone.com. |
Callback issues
| Symptom | Likely cause | Fix |
|---|
| No webhook arrives | Callback URL is not configured | Send your HTTPS endpoint to bulktext.ie@vodafone.com. |
| Vodafone cannot deliver callbacks | Endpoint does not accept POST or TLS requirements are not met | Ensure your endpoint accepts POST, supports TLS 1.2 where required, and returns 200 OK. |
| Duplicate callback processing | Handler is not idempotent | Store callback IDs or use notifyId plus timestamp/status to deduplicate. |
| DLR arrives late | Mobile network delivery status is delayed | Accept late DLRs and keep messages in an unconfirmed state until your timeout expires. |
| Verification hash does not match | Wrong verification key or hash input | Check the documented formula and confirm the verification key for your account. |
Legacy API issues
The v1 URL-encoded API returns plain-text status codes and messages, sometimes inside a 200 OK HTTP response. Always inspect the response body before treating the request as successful.
See Legacy API overview and the URL-encoded legacy endpoint in the Legacy APIs sidebar.