iphone - Why does my UITableView add another section for me when I insert an entry into an exist section? -

I use NSFetchedResultController and CoreData to manage my UITableView, but I have a problem. It's really confused me for two days, and I do not know how to deal with it.

I use two entities (group, contact) to store my data, and in my table view, divided into contact groups, this app works fine when the app is launched, But when I add a contact, which is one of the present group, the tableview adds a new section for me. It is not what I want.

I have tried two ways and hope to fix it, but ... First of all, I use the GRP relationship of contact segment because my section isolation. The result is not what I want. So I change the other, I add a new feature (GNIM) to group my contacts, I thought this is just because GRP is a relationship, so I use a feature that does not work either is.

Pleeeease help me

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It is difficult to tell without seeing the code, but when you add a contact and save it, then you are doing some calls such as the table [self.tableView reload] for example ?