After upgrade on 9/7/20, mobile network not working.

[NickWong]

Please tell us some basic information before asking for help:
Model Name: ASUS_X00TD
Firmware Version: PKQ1.WW_Phone-16.2017.2005.082-20200506
Rooted or not: NOT
Frequency of Occurrence: 9/7/20 updated till now
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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First updated informed was in 2/7/2020, after upgarded on 3/7 mobile net work not working. I just keep waiting for 3 days than get noted by system new upgraded avaliable. After this second time upgraded the problem solve work fine can use for mobile network.
Then till 9/7/2020 informed again by system for upgraded, than just follow the instruction to upgrade it . After upgraded this version (PKQ1.WW_Phone-16.2017.2005.082-20200506) after restart the phone than the mobile network back to problem again(no mobile network)till now(14/7/2020)....
Currently i only can connect office & home wifi to do my job... Pls help any solution for this.

[Christine_ASUS]

Hi NickWong
Thank you for your asking. Kindly try some stay-at-home troubleshooting tips below:
1. Please try reset Network: Settings>System>Advanced>Reset options>Reset Wi-Fi, mobile & Bluetooth
2. After you change your preferred network settings, does the situation remain the same? Settings>Network & internet>Mobile Network>Advanced>Preferred network type (2G/3G or 2G/3G/4G)
3. Could you still call or text to others? Only the mobile network has the issue or the whole SIM card couldn't work? Also, please try "the Factory Reset" 
Settings>System>Advanced>Reset options>Erase all data(factory reset)
Please note that once the Factory Reset is completed, all data, apps, settings and personal information will be deleted.

If you have any further queries, please do not hesitate to contact me.

[NickWong]

Hi Christine
No 1 & 2 - solution tried still remain the problem, can't solve it.
No 3 - i still can make call & sms to others like normal. I tried in "save mode" still remain the same problem.
If reset to "The factory reset" is it will back to the before upgraded the software version ? Because i suspected was the software problem, the second time updated problem solve...only the third times updated than back to the problem.

[Christine_ASUS]

Hi NickWong
Thank you for your reply. The Factory Reset will remain you in the same firmware version WW-16.2017.2005.082, kindly give it a try.