Can't set the movement speed in the third person blueprint, Can only get it!

Hi, I tried to drag the variable of the movement speed, but the set button wouldn’t work, only the get! - Which is a problem to say the least! - I then alt dragged it and it said read only, Should it be like that for an example? Or is it a bug? - By the way I do know what read only means.

Well thats because you dont want to Set a new Movement Component. You just need to change variables inside that Component.