God Fist Lee Sin (Self Cast W then Flash Bug)

God Fist Lee Sin (Self Cast W then Flash Bug)

As the title suggest, with the skin God Fist Lee Sin when you self cast W then Flash, for a brief second it's impossible to move. Not all the time but 4/10 i can say. Sometimes when you W then try to ward hop or just shield an ally. You suddenLee stop moving

Is this a common bug or am i the only one experiencing it ?