Hello  @Petrus127 ,

Welcome to our community.

Here are some troubleshooting steps to help get you back online:

1. Verify your APN profile settings
Log in to your router's web interface at http://tplinkmodem.net, then go to Advanced > Network > Internet and check if the Access Point Name (APN) settings are correct for your carrier. If the firmware update reset these settings, you may need to select the correct profile or create a new one manually.

2. Check the SIM Card Status
On the same web interface, go to Advanced > Status and confirm the SIM Card Status. If it shows "Prepared" but there is still no internet, the APN settings are the most likely cause — please revisit Step 1.

3. Factory Reset the Router
If adjusting the APN settings doesn't help, try performing a factory reset by pressing and holding the reset button for about 10 seconds until the Power LED starts flashing. Note: This will erase all customized settings, so please take note of any configurations you'd like to keep before resetting.

4. Additional note
If your ISP uses 464XLAT technology, you may need to manually create an APN profile and set the PDP type to IPv4 only, keeping other settings as default.