I've tried to 'fix' the IP of my Raspberry Pi Zero W in the local network by creating a DHCP rule in the router: always allocate 192.168.0.109 to the MAC address of the Pi. I use a D-Link router and by default the reserved pool for DHCP is 192.168.0.100 to 192.168.0.199. I tried setting the IP outside of that range but got the error "IP address for 'raspberrypi' should within DHCP IP address range".
The problem is that it almost never works, sometimes it starts with the 'correct' IP but then switches, sometimes it starts out directly with a different IP. When I check in the router DHCP client list the Pi lists with it's actual network IP but a different MAC than it's supposed to have. When I check on the Pi with ifconfig it reports it's actual network IP (but not the 109 one, different ones) but the original MAC (The one used to create the DHCP rule that is not respected).
So my issue is that with the MAC the Pi reports it should have an IP, but it has a different IP and the router also says that it has a different MAC than it should. I tried both methods from this post (both the /etc/network/interfaces and the /boot/config.txt, I even checked to make sure I don't have network-manager installed, to no avail). I don't know what to try anymore and the behaviour continues. Any ideas or help?
Edit: I also saw mentioned in some other posts so I checked /proc/cpuinfo for the serial numbers and they're not all zeros, they seem OK, and I bought it from an authorized reseller, so I'm thinking it's not a counterfeit hardware problem. Everything works fine, including the networking, just not the IP/MAC addresses...