Thank you for your asking. Kindly try some stay-at-home troubleshooting tips below:
1. Please try reset Network: Settings>System>Reset options>Reset Wi-Fi, mobile & Bluetooth
2. Does the issue appear after any system/apps' download or update? Please try to enter "Safe Mode". If the function works well in Safe Mode yet the issue remains out of Safe Mode, please check on any disturbance from the installed 3rd party apps.
# How to enter and exit "Safe Mode"https://www.asus.com/support/FAQ/1005163/
3. Please try with other sim card with different carriers. Does the issue happen in all carriers?
4. Please check your preferred network settings (2G/3G or 2G/3G/4G)
5. Please try SMMI test
Calculator> type ".12345+=">SMMI TEST>Single Test>SIM Signal Test/Wi-Fi Test
If any of the SMMI tests fails, indicating high possibility of faulty hardware, kindly bring your device to the nearest ASUS repair center for device checking: https://www.asus.com/support/Service-Center-All-Countries/
If it is impossible to access the service center during Covid-19 period, please try Call us: https://www.asus.com/support/CallUs