OK… As first… Don’t set axis twice… I mean… No MoveLeft + MoveRight… Just do a MoveH and put two keys inside with the ± values.
Second… Never do values other than ±1. I mean… Never do 100 or -100.
Change them to 1 and -1 and when you call the event, multiply it with a Variable… Best from the GameInstance… That way you can change speeds and values right from the game… Instead if struggling with them in the Input Preferences.
Third.
To your Question:
Do you have Input Events of the same type elsewhere in your Codes? Cause… If yes… And their events consume the input… the inout is gone for all other events… And so… Not fired anymore.
Second idea… Even if the mouse works… Try the EnableInput Node, placed in your Begin play… And connect your Player Controller as Input Caller… That way you make sure the PC is sending Inputs to the Actor, without struggling with the Auto Input Settings…