Help with CFrame.Angles and Functions with paramaters?

function M6Drotate(X,Y,Z)
    M6D.Transform = M6D.Transform*CFrame.Angles(math.rad(X),math.rad(Y),math.rad(Z))
end

Error: Workspace.Test.Script:27: bad argument #3 to 'Angles' (number expected, got nil)

(lines would be 27-29 in my script) (M6D is a Motor6D(a character joint)) I do not know why this error is occuring.

Any help will be greatly apprectiated!