Naps ?

My almost 5 month old seems to only want one nap a day. She sleeps from 7pm-9:30am (usually wakes once or twice to eat) and then has one long nap in the afternoon for about 2-3 hours. And then bedtime at 6:30. I’m reading that at this age they should have 3-4 naps 😳 What am I doing wrong? WHY ARE NAPS SO HARD