There used to be a "mobile" version of the dashboard (called
node-shri-dashboard, iirc) -- it was an incompatible fork of the main dashboard, sporting a background image of a mobile phone. Can you check the Palette Manager's "Installed Nodes" tab, searching for "dash"? You should only see one, namely the core version of
node-red-dashboard -- if there are others installed, they may be causing conflicts and should probably be removed.
Oh, and if you ever see
node-red-contrib-ui installed, that is the old version of the dashboard code before it was transferred over to Dave and the node-red team -- it too should be removed in favor of the latest dashboard module...