Unable to display list items in custom View after adding items to list through code

I can't say exactly (because you didn't provide any code), but it looks like that you're putting some loose values into your Person/Group column. When you re-save item, SharePoint resolves the issue, probably by re-parsing the value.

The point is, that actually SharePoint validation is occasionally not very good and sometimes you're able to set some incorrect (bad-formatted) values through SharePoint Object Model.

Please, review your code intently, paying particular attention to the fragment where the Person/Group column is getting filled.

The right scenario for setting up a Person/Group field value will be:

1. First of all, you need to retrieve ID of the user if you have his login name, the best option will be to use SPWeb.EnsureUser method (it searches for the user, and if user with specified login was not found, it adds him to site).
2. Having user ID, and having SPListItem object instance, you should set the field value. The most prudent way to retrieve the right field is to use the field's guid.

The code will look something like this:

var loginName = // pass user login name here
var fieldGuid = // pass your field Guid here

var userId = SPWeb.EnsureUser(loginName).ID;
listItem[fieldGuid] = userId;
// ... set other columns
listItem.Update();