Why does instantiate work for Visual Effects Graph but not Play()?

According to the documentation on visual effects graph there should be a working Play function for C# but it doesn't seem to do anything despite me having it all set up within my Input.GetMouseButtonDown if statement. Meanwhile though the standard way of doing things like using instantiate seems to work fine but I'm not sure why, anyone got any ideas?

For the record, the visual graph itself is set to single burst because it's a turret and that prevents it from firing constantly.