Zwiedorf H: 37cm, Women’s Wellington Boots

The boots looked just what I wanted and I ordered a UK size 6 (EU 39) from the drop down menu. When the boots arrived I put them on and they were tight so I checked the size and I had been sent an EU38. I returned them and ordered again and exactly the same happened so I gave up. I'm left with the feeling that whoever does the picking doesn't know their sizing. Why give the option of UK sizing if this can't be translated into EU properly.