How to notify users before the package association stops?

Remind the user of the downtime 3 days before the related downtime of the software package (the related downtime trigger number has been down for 2 days). SMS reminder, other products are based on the priority of fixed-line and broadband voice reminder, that is, fixed-line reminder and broadband contact phone have no fixed-line reminder. Voice can only remind one number. Reminder template (voice, SMS): As of XX: XX of this month, XXXXXXXXX has been in arrears for 2 days, and all numbers under the XXX package handled by this number will be shut down after 3 days according to the package rules. To ensure normal communication, please pay the fee as soon as possible. Please ignore this reminder if the arrears have been paid. For more service benefits, click "official website" customer service 95 below to answer your questions.