Xamarin error code 34018
<p>I've been dealing with this issue when I run my app via debug on simulator, as soon as I upgraded to the latest Xcode 8.0 and OS version 10.11.6. Error below:</p>

<p>Application Settings exception, Unable to store key CognitoIdentity:IdentityId:eu-west-1:<em>KEY</em>, got error: -34018.</p>

<p>Seems it's linked to the keychain but haven't got a solution on Xamarin yet.</p>