Hey, dev for An Outcry here. I have two ideas you could try to fix the issue you're experiencing:
1. Do you have a controller connected? Controllers might interfere with the keyboard controls of the game- If all else fails, the game is also playable with a controller.
2. There is a rare bug with the engine the game is made in where keys "stick" on the keyboard, interfering with any other keystrokes due to input being dropped. The developers of the engine are aware of this bug, and have offered a fix for it here:
https://steamcommunity.com/app/362870/discussions/0/541907867763056737/
Here's an official troubleshooting topic for this issue. I'm hoping it helps!