Girls, a year old, sleep problems started. I'm just freaking out, if b…

Girls, a year old, sleep problems started. I'm just freaking out, if before 15 minutes of rocking and he sleeps, now it's trash, just two hours, I shake from the thought that he needs to be put to bed, I sit and cry because it's so annoying, what should I do? Can you advise on how to transfer to self-soothing and generally what to do with him?