Been trying to conceive our second for almost 12 months 😢

I'm getting very depressed!! What's the deal??! I got pregnant with my first child so quickly! I'm trying to stay positive but it's so hard! I want a big family!! We only BD a few times during my fertile window. But we always do it a couple of days after I get my surge! ( we've started using ovulation kits.. We've used them about 4 months now) any suggestions on what I can do to increase my chance??? We also us preseed!!