No they are not... Miley Cyrus is the former Disney star and musician and is now engaged to Liam Hemsworth and Hayley Kiyoko also a breakout Disney star from Leamonaide Mouth is/was dating her co-star Adam Hicks from Leamonaide Mouth. She has also starred in 2 Scooby Doo movies where she played Velma
Miley Cyrus is not Haley Kyoko. It's just that the Haley Kyoko is using Miley Cyrus photo as her profile picture on Twitter. Check the tweets by Miley and those by Haley and you will notice the difference.