How to make mesh move along the path forward and backwards

Simples as the question, i want to make the mesh move along the Spline (path) forward and backwards depending on state of the player.

I think i don´t need to show my nodes because the problem is that i don´t know how to do it.

If i didn´t need this, i know i could use Timeline to make it move forward along the path, but for example, if the State B happens, i need this mesh stop where it is, and then start moving backwards along the path until the other far point.
I tried to use Event Tick along with a float, but this doesn´t work properly.


I got the solution by mysfel, i just multiply a float by 0.0001 every tick and if i want to reverse, just multiply by -0.0001.

But now i want to set a start point hehe.