Customer Center: Can I Turn off the "Change Username" Function?

Yes, you can add the following code to your CSS file - in some themes you can add additional CSS to be loaded last in the theme's configuration section. Or, you can edit the theme's style.css and add this code at the very bottom:

/* following code hides the "Change Your User Name" section in Customer _ Center */
h3.pp-section__divider:nth-child(3) {
 display: none !important;
}

div.pp-section__div:nth-child(4) > div:nth-child(1) {
 display: none !important;
}

div.pp-section__div:nth-child(4) > div:nth-child(2) {
 display: none !important;
}

/* End of code that hides change your username */