Communication regarding outstanding account

Our medical aid did not cover all the cost. The communication we received regarding this was an sms which I do not feel is adequate, it is not a credible method. The account was handed over to a attorneys and this was the first time I was contacted per e-mail and telephonically. Suddenly the amount was doubled. We have paid the account. I feel a reasonable effort should be made to communicate outstanding amounts. One sms is not enough.