weapon enchantment visual effect not working properly or not working at all sometimes

bought a vorpal enchantment rank 14 in auction house and equipped it, on C the visual wep effect is a constant shine but on gameplay the visual effect is blinking (i think like a rank 9) and sometimes no shine at all.
I tried removing the enchantment and equipping it again and tried disabling visual effect and enabling it again but
didnt work.
Was a very expensive enchantment so I think I deserve my weapon to be shining properly ^^
Thank you.