Magento 2 order error when trying to invoice or cancel
I've currently enabled just purchase orders so that I can test offline payment methods (other method will be authorize.net direct post, but that's not currently enabled).
I've created 2 orders now, and every time I try to cancel or invoice either order I get an error on the page "Request does not match any route". I don't seem to get any other error in the console. I'm not seeing anything in the debug log (and I'm in developer mode). What can I do to debug this error to figure out why it's rejecting any order modifications? This is Magento 2.2.3 EE.