R7000 can't access admin page anymore and DHCP IP Range changed on its own

I was able to determine the cause. It tipped me off when you said the IP range changes when there's a second device doing DHCP. I noticed there were new computers on my network when I looked at network file sharing. I use the Netgear Powerline device to get wired connections to my living room. What I believe happened is that my neighboring apartment unit recently set up internet and is also using a powerline device. I noticed my DNS suffix was changing to a different address which is the ISPs instead of my router. I put 2 and 2 together and realized my network was overlapping with his via the powerline. I never set up an encryption key on the powerline so it was still using default settings and connecting to my neighbors powerline. When I added the encryption key, the problem went away and my network returned to normal. Next time I should follow the instructions when setting up new network hardware. Oops