My TP-Link TL-WR841N router shows connecting..., Urgent help plz

I bought a new TP-Link TL-WR841N router from lowyat plaza unifi supported to replace my Dlink router. After I bought it and setup using the quick setup, it worked just fine. After few days of using I turned of the main power of modem n router to restart. Now in the status of router page showing Connecting.... the setup was exactly same as it before. I rebooted reconfigured but nothing is working. What should I do? Now I am back to old router.

Thanks