Without your code I have no clue
But I would guess that you shouldn't use the commit() function but instead sync() the store.
This is what i used to do back in the day
Code:
this.editor.on('afteredit', function(editor, changes, record, rowIndex) {
if (changes.passwordHash) {
record.set('passwordHash', base.SHA1(changes.passwordHash));
}
this.store.save();
this.store.reload();
}, this);
this.editor.on('canceledit', function(editor, forced) {
if (this.store.getAt(0).phantom) {
this.store.remove(this.store.getAt(0));
}
}, this);