This video shows you how to send automated SMS every day/business day.
Code shown:
contact_record = zoho.crm.getRecordById("Contacts", contact_id);
current_time = contact_record.get("Next_Time_To_Send_SMS");
one_business_day_later = current_time.toTime().addBusinessDay(1);
update_payload = {
"Next_Time_To_Send_SMS": one_business_day_later.toString("yyyy-MM-dd'T'09:mm:ss")
};
update_resp = zoho.crm.updateRecord("Contacts", contact_id, update_payload);