your isp's dhcp does not function properly ASUS ROUTER

Just moved in to a new apartment and got a xfinity setup here it came with the provided infinity router but I didn’t like it so I went and bought a ASUS router, hook it up and had xfinity set up new MAC send a new signal and everything but on there end they could not find my router. So now I’m on my laptop have Ethernet cable connect to the router and my laptop went on router.asus.com to check my router and got your isp's dhcp does not function properly, then tried a lot of configuration and your isp's dhcp does not function properly went away and internet disconnection is now on instead of your isp's dhcp does not function properly, tried resending the signal but still nothing work pls help