New WiFi devices will not connect after new router installed

Have the same issue since I replaced a cheap Pix-Link AP with a TP-Link EAP615-Wall (same SSID and password the previous AP).
Most of the devices did reconnect without any issue, but my DW2-Wi-Fi-L refuses to reconnect, even deleting and trying to re-connect doesnt help.
Then I tried to connect a Sonoff R2, get detected, but at the process registering to wifi, it fails.
Im am 100% sure that it is related to the AP setting but cant find it. When I pair trough another AP or the old-one all is OK.
I canot find in the TP-Link settings something related to “access control” can any one please help.
Of course I have the latest firmware and uncheck MAC filtering and the basics. But seems more default parameters are critical. Could it be one of these ?

Could anyone please guide/help me ?