Hello ladies, I dont know what to do at this point need advise. My 20 month old was going to sleep…

Hello ladies, I dont know what to do at this point need advise. My 20 month old was going to sleep at 9 mp and wake up at 8 am . Than went to daycare , where she would rake her nap . but past week she wont go to sleep at 9 anymore or anywhere close . Its more 12,1,2,3 am she is not sick hungry , diaper is clean . I tried rucking her to sleep like always she doesn't want it she is not much of a cuddlier i even took her for a ride . The doctor said maybe her teeth and to give her some Baby Tylenol and that didnt help . Any suggestions? Did anyone go through this ?