@PolarBear68N Hi, that is noted and if still no any SIM card can be detected any more, you could claim warranty and get it replaced with the retailer.

@Aca-24_ Do you still remember the password of your TP-Link ID? If so, please try to login the Tether App or Deco App with your TP-Link ID and its password to see if it works.

@Dev192 Hi, please provide more details about the issue, do you mean WiFi can be seen but unable to join any more? what is the error message? If possible, you could connect to the router via Ethernet...

@Alicia000001 Hi, are you using Tether App? If your router has been bound to previous account, please unbind the router from your account first, go to Tools->TP-Link ID, tap the three dots on the...

@Sakib_777 Hi, it seems that this model doesn't support Tether App, you could also double check the Tether App compatibility list: Tether Compatibility List

@FabianAbernal88 Please try admin in lower case to see if it works, if not, please try reset the router to factory defaults again by holding reset button for about 10s. By the way, was this device...