that fight is very lopsided because your archon is only a luminous
archon conjurer needs to flee every now and then, to let the archon heal you up
dismissal is king in conjie fights. archon keeps you alive for more dismissal attempts. dismiss enemy elemental (don't accidentally target your own), then the devil.
use your familiar if it's at all tanky. best time to use it is to absorb the hits from their elemental before you dismiss it.
don't use staff of striking prog when you're losing. flee and heal up instead
remember to use kaubris anchor on the thing you don't want dismissed, which is probably the earth elemental