Name wont change

I changed my username about a day ago. After that I noticed today that my name has not changed in the launcher, I didn't think much of it but as soon as I went over to my realms it said "Restart Minecraft" and that's what I did. I turned off the launcher and the game waited about 2 minutes and hopped back on. The name was still unchanged and when I went to my realms again "Restart Minecraft" I hopped into a singleplayer world and when I loaded in the world I used the text chat. MY NAME WAS STILL THE OLD ONE. I've been struggling with this for hours I would love some help with this.