Bed time struggles

Hey everyone! My boy is 2 years old and for the last year his been amazing with his sleeping schedule, it was pretty strict, he would wake up at 8am, nap from 1pm to 2-3pm, then to down for bed at 8.30. He has stuck with it.

For the last 2 weeks it's been a struggle, he still has his naps but bedtime is a struggle, he doesn't want to sleep! I've put the bedtime to half 9 now to see if it helps but he literally lies there wide awake, cuddles, books or anything doesn't help.

Ive also purchased a blackout blind to go behind our curtains and the temp in our room is perfect.

He would happily lie in a pitch black room silent for hours.

The first success we've had was yesterday, he didn't want a nap so I didn't force him, he got grumpy obviously but I kept him entertained, at 8.30pm he fell asleep within minutes, woke up at 9am, but he did go for his nap today so it's currently 10.30pm and his still wide awake.

What do you guys think I should do? I was thinking of stopping the naps but what if that messes with his mental development?

I need help x