Has to do probably with the miui sms activation.
A sms has to be send in order to combine your mi account with your number.
Can you send sms with your card? It is an one time action.
.Si, lo he intentado varias veces, he puesto saldo y aún así me marca error. Cambie el e-mail de la cuenta, me manda código de activación, pero la app de SMS no me marca el error. Podrá ser que con otra app de SMS funcione?
.Yes, I tried several times, put a balance and still make an error. Change the email of the account, it sends me the activation code, but the SMS application does not mark the error. Can you be with another SMS application to work?
