www screws up domain mapping?

Ok. After a long wait with LunarPages support I am up and running. I even got domain mapping to work. Sort of…

If I go to https://jlptpass.com/ everything works as expected.

If I go to https://www.jlptpass.com/ I am redirected to the LunarPages homepage…

I don’t care about having www in the url, but I want it redirect properly if someone types that in.

Any ideas how I can fix this or why it is happening? While my other issues were the fault of LunarPages, I think this one might be the plugin? I googled around a bit, but came up short.