Line and account changes are more consequential than routine profile edits. Combine device context with authentication and transaction approval.
Evaluation approach
A phone number is not a permanent personal identity. Number and device changes belong in the lifecycle. Bind sensitive changes to server authority, current sessions and approval.
Application example
During device replacement, review old access, sessions and trust records together. Do not transfer the previous device's positive result automatically. Provide secure recovery.
Limits and considerations
SIM and device changes are not always attacks. Permanent blocks based on one signal can increase support burden and lost access.
Checks and decisions
- Separate identity from phone number
- Model device changes
- Test recovery independently
Review line, contact and trusted-device changes as well as sign-in.
Sources
The primary references above provide the technical basis. Example workflows and evaluation suggestions are this publication’s explanations, not independent test results for a particular product.