i was scamm

hi i was scamm by 0v3rwh3lming....he got 1 sardonyx for sell and is binned....i wanna pay him 8.5b for him...i trade my MC2 seg....was full slot whit 1xsardonyx inside....he say give me back after put the gem.....but he go off and dont give me back the helm....pls make somthing....i wanna back my helm....my seg is CrazySeg