Baby sleep difficulties


We were having problems getting baby to nap and sleep so we thought it's cuz he doesn't need two naps. So these few days we've been cutting his naps down to one. But instead of easier, he's been more difficult. One night it took three hours to get him to sleep and today it took two. Omg.

Is it cuz he actually does need those two naps or is he still adjusting to one nap a day? We are going crazy.

Hes 15 months btw