Please tell us some basic information before asking for help:
Model Name: ASUS ROG PHONE 3
Firmware Version: LATEST
Rooted or not: NOT
Frequency of Occurrence: SINCE 1 OCTOBER 2020
APP Name & APP Version (If your issue relates to the app):
In addition to information above, please also provide as much details as you can, e.g., using scenario, what troubleshooting you've already done, screenshot, etc.
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SIM 2 has been inactive since 1 October. Who had the same case?