Help with scratching.

[Bewul]

As the title says, I am having incredibly difficulties scratching the stickers at the start of battle on keyboard, I will guess something was changed in the time between episode 4 adn 5 release? I can barely scratch one or two when I used to be able to scratch all. I am using keyboard, no controller. Any fix or help? I am just on episode 2 (replaying the game) and it is very annoying.