Bedtime

I can’t for the life of me get my LO to stay in bed! This has been going on for awhile now. We use to give her two cups of milk and put to bed and we wouldn’t normally hear another peep till morning. Lately, we’ve cut her down to one cup of milk than bed. She gets out of bed 9394738182 times before finally exhausting herself and falling sleep. I’ve tried taking her prized possessed blankets, shutting the door, rewarding treats in the AM, everything!! What can I do !? Her bedtime use to bed 9pm but I switched it to 7 these last two night thinking maybe she’s over tired and acting out??? I don’t know anymore