Islamiat O level Time management

Sir have been facing a problem with time management in o level islamiat. I have tried to fix it by practicing but couldn’t make it any better. My on average a 10 mark question takes about 20-25 mins, but everyone says that it must be with 15 mins, which seems impossible for me. I cant go over it and wonder whats the problem, whether its the too much content that i put in or my speed. I write to the fastest speed i can but cant make it. Plz help!