Could you provide a bit more information?
Assuming you have implemented the context mapping. When pressing whatever button is mapped to this input action, the Boolean is held R will be set to true. It will not unset when you let go, nothing will happen. If you want to unset it when the button is released, you need to add a set to false to the onReleased event pin in the event. The name might be different but it will be similar. Press the white arrow at the bottom of the event to see the other pins available.
Easiest way to test this is to add print strings to every execution pin, to print the name of the event, and it will tell you what is happening when you press the button