Tiered ruffled dress EU XL. More like medium

Never worn. Purchased and does not fit... states it is an EU XL which is a European XL.. which is why it is smaller .. it’s a MEDIUM.. I didn’t pay attention to the size equivalents when I ordered it 95% viscose and 5% Lycra I’m 5”9 and this goes right above my knees Aside from trying on this has never been worn for more than a few minutes