Manual connection to the SSID?
Make sure they have different channel?
Resetting and configuring from scratch?
Also, how do you connect the AP to the router--wired or wireless? Have you tried both? It might be the cause.
Hi, I have a wireless router (TP-Link AC1900) at home in my closet on the 2nd floor. Yesterday I connected a wireless access point (TL-WA-901ND) to have better coverage for spaces on the 1st floor that do not have good signal from the router. Now with AP connected, for 2 laptops and 1 desktop I can no longer see the SSID from the wireless router, I can only see SSID (different from the router one) from AP. I have another laptop that can still see and connect both SSID though, but I noticed the signal strength from the router became weaker than before. My cell phones can also see both SSID. what is going on here? Why I can't see wireless from the router from those 3 computers? Thanks and desperately need help!

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