First mistake you made. Didn't have a Seed cover
I see so many try seed patches in lawns like you did and get the same results
Go re seed the areas and shake out some wheat straw apply it thin where just covers the ground make sure there no clumps.
I know some say on here will say no need put straw down just compost and water. But who can go by each day to water the spots with straw it will hold the moisture and will hold heat in longer. So the seed can germinate faster.
Snyder's New Lawn Service Inc.