Smooth intepolation movement

Hi everyone.

Need help to make my actor to smooth out the stopping movement instead of immediate stop.

Refer to my attachment, I use these BP nodes to move my actor on Touch Screen Input.
I create a separate function and later use Event Tick to call the function in Event Graph.

I tried to use Finterp to make my actor to slowly stop the movement once touch finger remove but I have no luck in doing so.

Could someone please show me the correct way for how add smooth stop movement on my actor once the touch finger remove. Thank you very much.