Sencha Touch 2: localstorage creates multiple ids - extjs

Question

My User has the following config:
identifier: 'uuid',
proxy: {
type: 'localstorage',
id: 'tm-user'
}
But in my localstorage the following is shown:
Why is the id added to the tm-user key everytime I save the user profile?
I only overwrite the user everytime if that helps?
// create user
var user = Tm.model.User.create({
id: response[0].id,
...
});
user.save();
EDIT: full model requested:
Ext.define('Tm.model.User', {
extend: 'Ext.data.Model',
config: {
hasMany: { model: 'Tm.model.Exam', name: 'exams', autoLoad: true },
fields: [
{ name: 'id', type: 'int' },
{ name: 'username', type: 'string' },
{ name: 'email', type: 'string' },
{ name: 'nameFirst', type: 'string' },
{ name: 'nameLast', type: 'string' },
{ name: 'syncedAt', type: 'date', defaultValue: null }
],
validations: [
{ field: 'id', type: 'presence' },
{ field: 'username', type: 'presence' },
{ field: 'syncedAt', type: 'presence' },
{ field: 'email', type: 'presence' },
{ field: 'email', type: 'email' },
{ field: 'username', type: 'length', min: 3 }
],
identifier: 'uuid',
proxy: {
type: 'localstorage',
id: 'tm-user'
}
}
});

Answer 1

Change the following (if you're using UUID type should be string, not int.
{ name: 'id', type: 'string' }
And change identifier definition like:
identifier: {
type: 'uuid',
isUnique: true
}
Update
Since you're receiving Ids from the server and they are not UUIDs you might try the following. Change identifier configuration to this:
identifier: {
type: 'sequential',
isUnique: true
}
and of course type of id should be int in this case. If that doesn't work however I would recommend still use first approach (using uuid) but store id you're receiving from the server in some different field (item_number for example) and let ST handle unique UUID field.