I receive E-Mail notifications by Duo Security that my Telephony credits are running low. (I have used 2FA via SMS; meanwhile I have chosen a different system.) I do not want to receive these E-Mails anymore. But when I want to login with my password, Duo wants to make 2FA and I get the following message: “Error sending SMS: Insufficient telephony credits.” So how do I stop this? Basically I do not want to use Duo Security anymore and delete my account.