The blue light keeps flashing quickly and won't pair on the App after QR code scanning successful.

1. If the camera didn't indicate "wifi connection failed"during setup, the reason could be the camera didn't obtain an IP address from the router;Please make sure the DHCP configuration is enabled on router settings and chekc whether you've turned on the MAC address filter or other filter settings on router.  
2. If camera indicates"wifi connection failed", please find the corresponding troubleshooting methods to check it.