Duel Weilding Sword Glitch

Put the summary of the bug you're having here
Ok so when duel wielding a "Sword" and right click it will put the sword in blocking mode. (As it is suppose to do.) However when click fast it glitches out and makes the sword just appear to move up and down.
What I expected to happen was...:
Just a graphical bug i believe, the sword is suppose to "block or shield the player"
What actually happened was...:
(Said in summary)
Describe what happened here

Steps to Reproduce:

1. Spam right click on mouse and it should appear to move up and down.
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