3dRavens method would need you to implent it using behaviour trees. Because you are not usign any, I suggest that you use the “Move Component To” Node to rotate back in the Event called from the timer.
This node moves an component of the actor to a certain position and roation. If the component you move is the root component, you move the entire actor. Also the node comes with built in interpolation so it rotates the actor over a given time. Makes it look smooth and it will not jump to the rotation as the “Set Rotation” Node would do it.
To implement it you would need a variable wich holds the default rotation of the actor. Which you then use as the rotation for the “Move Component To” node.
You also need to use the current location of the actor as the traget location for the “Move Component To” node. If you do not, it will move the entire actor to the origin.