SMS-Authentication fails (Bulgaria)

• I have searched open and closed issues for duplicates
• I am submitting a bug report for existing functionality that does not work as intended
• This isn't a feature request or a discussion topic

Bug description

Error when trying to register. "We are unable to send an SMS to your number. Please try again in a few minutes."

Steps to reproduce

• Just download the app and try to register..

Actual result: No SMS being sent with the verification code, can't register using any other way, no "Call me instead" button on the iPhone app or grayed out on the Android version. I've tried to register on both android and iphone with the same results , even borrowed a sim card to double check , I've tried 1 attempt on each device to prevent lockout and it's not working.

Expected result: You should get a verification code and use the app normally.

Screenshots

Device info

Device: iPhone XS

iOS version: 18.7.10

Signal version: 8.28.0.1859

Link to debug log

org.whispersystems.signal 2026-09-16--15-20-14-575.log

Edit

I have tested the 8.29 version which released couple of hours after posting this, with this log (still not working)
https://debuglogs.org/ios/8.29.0/24a9d0390fdc75ae3ecea2662d99a7298aea69a3dcaa34d7297fa2b703f1d3e2.zip

Start with the attached iOS debug logs and reproduce the failure in the registration flow using the reported iPhone and Signal versions. Trace the SMS verification path for Bulgarian numbers; done means registration receives a verification code or provides a working fallback instead of the reported error.