See “Manage your Memojis” here.
How to use Memoji on your iPhone or iPad Pro - Apple Support
Use Animoji and Memoji in Messages on iPhone
Use the Messages app to express yourself with Animoji and personalized Memoji sticker packs that match your personality and mood. On models with a TrueDepth camera, you can send animated Animoji or Memoji messages that record your voice and mirror your facial expressions.
Create your own Memoji
You can design your personalized Memoji—choose a skin color and freckles, hairstyle and color, facial features and headwear, earrings, glasses, and more. You can create multiple Memoji for different moods.
In a conversation, tap , then tap .Tap each feature and choose the options you want. As you add features to your Memoji, your character comes to life.Tap Done to add the Memoji to your collection.
To edit, duplicate, or delete a Memoji, tap , tap the Memoji, scroll to the bottom of the sticker pack, then tap .
Clarification question - have you tried changing your picture in the Contacts app and then going to Settings/Your Name and change it there? I think you might have, but I'm not sure.Try a restart.Try a forced restart.Reset Device
Hello Eric Root,First, thanks for the reply.As I could not find a solution I try to delete the accounts from the iphone and I solved the problem.I think the problem was that my icloud account and my Apple ID account weren't very well synconized.I deleted the ID apple from the IOS (before gmail) and from the Icloud, and i login only with the @icloud.com, and now all works fine (can upload profile pictures and connect mail from icloud).One more time, thanks for the reply!Sincerely,Bispo
You are welcome. Good troubleshooting.