Virtual box tweaking my mellon.

Hi

I’m enrolled in an online course to learn Windows Server 2016. Built the virtual server and 1 vm workstation. I have a pool of ip address to hand out and 1 reserved ip to test system. When the static ip for the workstation is removed on the workstation the ip picks up some really odd ip, nothing even close to the network ips in the scope. I can’t tell if its a vb glitch or if I’m missing something. Losing my mind.