phone fails to obtain IP address

My brand new Samsung J7 phone (model number SM-J700H) fails to obtain IP adress from my Netgear extender WN3000RP. The phone connects well to the router (Arris) and establishes an internet connection. Also, other devices (ipad, my former mobile phone) connect well to the extender and establish an internet connection. So the problem seems to be between extender and the phone. I tried changing the IP address to static; the phone connects to the extender but there is no internet connection established. What could be the problem?