AWS Client VPN endpoint connection from mobile phone

Good Day, I am getting "Authentication Failed" error when attempting to connect to AWS Client VPN endpoint from a mobile device. Based on https://docs.aws.amazon.com/vpn/latest/clientvpn-user/android.html "OpenVPN" client was installed on iphone device and configured with the same configuration profile that works perfectly fine on Desktop with "AWS VPN Client" app. The authentication is configured as federated going against MS Azure AD (SAML), No Client Certificate is being used. In OpenVPN client logs we are getting "AUTH_FAILED Invalid username or password". Is there anything that can be done about this? Thank you, Sergey