You can outgrow a nickname without hating the kid who earned it.

Names attach to a particular year of your life, and you are allowed to move past the name without disowning the person who had it. The kid who earned it was doing their best with what they knew then, which is all anybody does. Leaving the nickname behind is a change of clothes rather than a verdict on who was wearing them.

Tell people the name you use now, plainly, without a speech about why. Correct it once and then let repetition do the work. If old friends keep the old one, that is usually affection rather than resistance.