Issue with Firebase Phone Authentication Not Working with Celcom Malaysia Carrier

[PSP HTP]

Hi All,

I am reaching out regarding an issue we're encountering with Firebase Phone Authentication. Users from the Celcom Malaysia mobile carrier are not receiving the TAC (SMS verification code) during the authentication process. This issue seems isolated to Celcom users, as other carriers in Malaysia are not affected.

Details of the Issue:

• Error Code: SmsRetrieverHelper: SMS verification code request failed: unknown status code: 17499 Error code: 39
• Firebase Auth Log:
  
  
• The number of failed attempts seems to accumulate quickly with repeated retries from users, even though we are well within the limits for sign-ups and requests per hour (based on Firebase console usage data).

Steps Taken:

• We have verified that the Firebase quotas are not being exceeded and that other mobile carriers (such as Maxis and Digi) are working without issues.
• We have tried different devices and network conditions to rule out local device problems.

Given that the issue seems specific to a carrier, I would appreciate any insights into:

1. Whether Firebase has any known limitations or issues with Celcom Malaysia.
2. How we can investigate further or provide you with more diagnostic logs to pinpoint the root cause.

We would greatly appreciate your assistance in resolving this issue as soon as possible, as it impacts a significant portion of our user base.

Thank you in advance for your help.