I feel like a failure 🥺

My 16 month old doesn't sleep for nothing!😫 No matter what i do he doesnt sleep. The earliest can get him dowm is 3am. No matter if I take naps out or only do one morning nap he still will not sleep until 3am and up from 8-10am. I tried waking him ip every morning at 8am and nap around 1030, sleeps for a hour or two and then up all day. Didnt work. Called his doctor qnd she told me no melatonin but to try benadryl, he gets very hyper from benadryl for some odd reason. I just dont know what to do anymore. I just want him to sleep, to get a good night of rest. Its been going on for a month already and nothing is working.