kSecAttrIsPermanent not persisting RSA keypair

Hello! I am trying to persist my RSA keypair generated with SecKeyCreateRandomKey. I am able to create the keypair with and retrieve the keys while the app is open:

var err: Unmanaged<CFError>?
let privateKeyAttr = [
    kSecClass: kSecClassKey,
    kSecAttrKeyType: kSecAttrKeyTypeRSA,
    kSecAttrKeySizeInBits: 2048,
    kSecPrivateKeyAttrs: [
     kSecAttrIsPermanent: true,
     kSecAttrApplicationTag: "tag"
    ]
  ] as CFDictionary
    
   guard let privateKey = SecKeyCreateRandomKey(privateKeyAttr, &err) else {
    return
   }

but when the app is killed and opened again, I am unable to retrieve the private key and SecItemCopyMatching returns -25300 errSecItemNotFound :

let storeAttr = [
   kSecClass: kSecClassKey,
   kSecAttrApplicationTag: "tag",
    
   kSecAttrKeyType: kSecAttrKeyTypeRSA,
  
   kSecReturnRef: true] as CFDictionary

var item: CFTypeRef?
  var key: SecKey
  let res = SecItemCopyMatching(storeAttr , &item)

  if (res == errSecSuccess) {
   return item as! SecKey
  } else {
   return nil
  }