Can't change Emblem

are you only using the unlocked items because if you are using locked it wont be saved 

try this steps this is if you are using only unlocked items 

1.log out and log in to battlelog and origin

2.delete your browse history

3.try a different browse 

4.re-install origin

5.click on repair install in bf4 game client in origin 

6.update your origin and have the latest battlelog pluggin 

7.update your driver

if non works contact Origin/EA support they will gladly help you whit this problem 

 https://help.ea.com/en/origin go here press contact as give information press i still need help at the bottom of the page and then press start live chat and you will get a live chat whit an EA agent that will be glad to help you

 if any of this helps pleas give XP to my account thanks