Problem authenticating username/password stored in Keychain

I am, at least, per success of the operation able to store a username and password in the keychain using the "addUser" function in the code below. I then when doing a login call the "authenticateUser" function but I get a -25300 error (errSecItemNotFound). I'm close here but missing something. Any help would be appreciated.

class func addUser(username: String, password: String) -> Bool {
            
    let serviceName = AppValues.appName // Replace this with a unique identifier for your app
    let account = username.data(using: .utf8)!
    let passwordData = password.data(using: .utf8)!
            
    let query: [CFString: Any] = [
       kSecClass: kSecClassGenericPassword,
       kSecAttrService: serviceName,
       kSecAttrAccount: account,
       kSecValueData: passwordData,
       kSecAttrAccessible: kSecAttrAccessibleWhenUnlockedThisDeviceOnly
       ]
            
    // Delete any existing items with the same account before adding the new one
    SecItemDelete(query as CFDictionary)
            
    let status = SecItemAdd(query as CFDictionary, nil)
            
    guard status == errSecSuccess else {
        evaluateKeychainError(errorCode: status)
        return false
    }
            
    LogEvent.print(module: "Authentication.keychain.addUser", message: "\(username)/\(password) added successfully.")
    return true
}
        
class func authenticateUser(username: String, password: String) -> Bool {
            
   let usernameData = username.data(using: .utf8)!
            
   let query: [String: Any] = [
      kSecClass as String: kSecClassInternetPassword,
      kSecAttrServer as String: AppValues.appName, // Replace with your server or app identifier
      kSecAttrAccount as String: usernameData,
      kSecReturnData as String: true,
      kSecMatchLimit as String: kSecMatchLimitOne
      ]
            
    var result: AnyObject?
    let status = SecItemCopyMatching(query as CFDictionary, &result)
            
    if status == errSecSuccess,
         let passwordData = result as? Data,
         let retrievedPassword = String(data: passwordData, encoding: .utf8) {
         LogEvent.print(module: "Authentication.keychain.authenticateUser", message: "\(username)/\(password)/\(retrievedPassword) authenticated successfully.")
                return retrievedPassword == password
         } else {
            LogEvent.print(module: "Authentication.keychain.authenticateUser", message: "Error \(status)")
            evaluateKeychainError(errorCode: status)
            return false
    }
}