Cuenta Kai is free and does not process payments, so there is nothing to refund here.
Purchases are made inside each Kai product (plans, KaiCoins, passes) and are governed by that product's refund policy, published on its own legal page. There you will also find the right of withdrawal under Colombian law Ley 1480 de 2011, where it applies.
If you paid for something in a Kai product and cannot find its policy, write to us at mauricio.zuniga@kaistrategylab.com and we will take you to the right page.