TodayStatements and renewal notices go out by bulk SMS at a flat rate whether anyone reads them. If a member disputes being contacted, there is no proof they ever agreed.
With SemaStatements, reminders, renewals and login codes on WhatsApp, sent only to members whose opt-in is recorded. Repayments are collected by M-Pesa from the same conversation, into your own paybill, and confirmed with M-Pesa before they show as paid.