DLink Managed Switch - change management VLAN - What am I missing

I decided to crosspost here, as its a bigger community than /r/Network

I am running 99% Ubiquiti Network. USG3 as main router, a few switches, and a few AP's.

VLAN1 - 192.168.10.x - everything used to be on - moving everything off this eventually. I understand vlan1 is bad - thats ok, ill get there

I made a new VLAN5, DHCP 192.168.2.x etc. This is my management network, as I was told it is good practice to have that stuff on their own VLAN. Both the switches and the AP moved to the new network - works great.

VLAN12 is guest - 192.168.100.x - all good and working fine.

I happen to have a small 8 port managed Dlink switch (DGS-1100). It was setup as 192.168.10.20, but I am going to move the switch into VLAN5, and tag/untag ports accordingly. Cord is plugged into eth1

I change the switch to DHCP, grabs a new IP 192.168.10.159 or something. Cool. I go into VLAN area, setup and tag eth1 as VLAN5. It also is tagged as 1 and 12. So now eth1 is tagged as 1, 5, and 12. Still going well.

I go into the management VLAN area, which is currently disabled. Enable, and then it gives me a dropdown menu, to choose 1, 5, or 12. I choose 5. The end. It doesn't pull a DHCP lease from the router, it just disappears. No longer on vlan1 as either 10.20 or 10.159. I have to power cycle it and then it reverts its settings.

Im at a loss here to how to get it to be assigned to vlan5! Any help is appreciated.