Ring doorbell 1 setup issue

Setup in my Ring Doorbell 1 kept failing when tried to connect to my network. I tried with different kinds of modems and routers. Mode is 2.4 for sure. Wifi modem and routers are not far away while trying to complete the setup. Speed are high and over 2Mbps. Test the network internet and it's working fine by browsing websites. Hard reset was performed too by pressing the orange botton for 15 sec. It keeps flashing white to the left without completing the setup. I couldn't crack this one up so, please help!!