Baby sleep

Hi Mummies, my LO is 11 months but still not sleeping through. She only nap once in daytime (3hrs nap). Her last feed will be 12am and she will finish 200-250ml of milk. But she will still wake up 3.30am and ask for milk? And after finishing her milk she will refused to sleep back. By the time she sleep back, 5.30am, I will have to wake up for work soon. Can mummies share with on some tips? And shld I feed my baby any supplements? If yes, any recommendations?