Unique identifiers on iOS Phonebook are not as expected - ios

Question

I am using the new version of retrieving contacts from the Phonebook on iOS. There is a problem with the unique identifier, which is returned by the first query. Normally the unique identifier is a UUID, but sometimes it is appended by “: ABPerson”.
Querying the Phonebook API with this identifier works sometimes, but not always. Does anybody know, if there is a way to avoid this behaviour?
Currently, I try with a safeguard of two queries. The first is using the identifier as is, the second (if the first fails) is to use the identifier stripping the “: ABPerson” extension.
The first query used is:
class func getAllPhoneBookContacts() -> [PhonebookContact] {
let contactStore = CNContactStore()
var contacts = [PhonebookContact]()
PhoneBookContactsHelper.requestForAccess { (accessGranted) -> Void in
if accessGranted {
let keys = [CNContactIdentifierKey, CNContactPhoneNumbersKey]
do {
let fetchRequest = CNContactFetchRequest(keysToFetch: keys)
try contactStore.enumerateContactsWithFetchRequest(fetchRequest, usingBlock: { (contact: CNContact, _) -> Void in
for phoneNoLab in contact.phoneNumbers {
if let phoneNo = phoneNoLab.value as? CNPhoneNumber,
normalizedPhoneNumber = PhoneNumberNormalizer.normalizePhoneNumber(phoneNo.stringValue) {
let pbc = PhonebookContact(contactID: contact.identifier, phoneNumber: normalizedPhoneNumber)
contacts.append(pbc)
}
}
})
}
catch {
NSLog("Unable to fetch contacts.")
}
}
}
return contacts
}
Accessing a certain contact again later by the identifier is done by:
class func getContactNameByUUID(identifier: String) -> String?{
var name : String?
PhoneBookContactsHelper.requestForAccess()
{ (accessGranted) -> Void in
if accessGranted {
let contactStore = CNContactStore()
let keys = [CNContactFormatter.descriptorForRequiredKeysForStyle(.FullName)]
do {
let cnc = try contactStore.unifiedContactWithIdentifier(identifier, keysToFetch: keys)
name = CNContactFormatter.stringFromContact(cnc, style: .FullName)!
}
catch _ {
NSLog("Could not fetch contact with id \(identifier))")
}
}
}
return name
}
I am using iOS 9 and tested on simulator and various iPhones and the unexpected behaviour is present everywhere.