Hi there!! :)
A baby's natural sleep cycle starts from 630-8pm. So it will be better to bring the night sleep time earlier because their bodies will naturally get tired and they will be more sleepy at this timing. If you miss this timing, your baby will be overtired hence she's resisting the sleep.
Because your baby now sleeps 9-10pm, should try to slowly make the bedtime earlier. Try to make bedtime at 8pm first. That means the last nap should end by 530pm.
Also make sure there's ample nap during daytime. Especially the noon nap because this is the most important nap - restorative nap. Sleep begets sleep. Dont listen to people who stops baby from napping so as to have good night sleep. No such thing.
Jiayou!!
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