it may be the longer naps that are the calprit. He's getting more sleep during the day, and for some babies, this causes them to wake at night.
My LO is like that. For exaple, she has a 30-45 minute nap in the morning, a 2 hour nap around noon, and another 30-45 minute nap in the afternoon (usually an hour before bedtime) For her this works. If she sleeps longer during the days she's up all night, with this routine she sleeps 7pm-7am.
Keep perservering and you will get there. It takes time and he may need to change his internal clock.
Your doing all the right things. Keep it up
