@tkurtulus Check this post for recommended steps.

@FishhyFishCakes The only way to separate users in different networks is to use the Multi-VLAN mode configuration for TL-WA1201.

@ujjal1960 To reset your router to its factory defaults press the reest button for about 10 seconds, then re-configure from scratch. The default one is admin (all lowercase) for both username and...

@SabbyZ If you've reset your C20 to its factory settings here's how to configure from scratch.

@Joest When in AP mode the device doesn't show its advanced menu but some of its features configured in router mode still work in AP mode - details.

Here's a feature request for that matter. Anyone interested can upvote this request for implementation.