Telefónica is one of the largest telecommunications companies in the world. In Colombia, it operates under the Movistar brand, serving millions of mobile and fixed-line customers across the country. At that scale, billing is one of the highest-volume drivers of customer contact, and one of the hardest to automate well. Customers want to understand why their bill changed, what charges are new, and whether a payment has gone through.

Telefónica Colombia had already tried to solve this with AI. They had evaluated over 20 providers and had an AI solution in place, but it wasn't working. The results were underwhelming, improvements were slow and difficult to introduce, and the vendor couldn't scale to new use cases. Telefónica Colombia's existing AI solution served only land lines but not broadband customers, leaving a customer segment entirely unserved. After years of stagnation, Telefónica needed a replacement that could actually move.

From kickoff to production in three weeks

The initial ask was modest: prove that Wonderful could match what the existing solution was already doing. However, discovery revealed that the existing solution’s performance was subpar, which highlighted a significant opportunity.

Telefónica had multiple APIs that were underused and not properly connected to the agent. The same billing use case was already being handled by human agents on WhatsApp, creating a clear path toward a true omnichannel model. Authentication, call handling, and post-call surveys were all fragmented across separate systems, each handoff creating friction.

Building it

The Wonderful agent handles bill explanation and price increase clarification across voice and WhatsApp. When a customer calls, it can compare invoices across two billing periods, explain what changed and why, whether there’s a tariff adjustment, a plan change, added benefits, a late payment penalty, and confirm payment status and dates. It also provides each customer's specific payment reference number and identifies any reconnection fees or additional charges on the account.

The agent now serves mobile, fixed-line, and convergent customers: the full customer base, not the limited subsegment the previous solution could reach. Post-call surveys are integrated directly into the same interaction rather than handled by a separate system.

Impact

• 91.5% containment rate on eligible interactions

• Average call duration under 2 minutes

• Average Handling Time was reduced by 50% compared to the previous AI solution

• Call volume scaled x2.5 in two months across voice and WhatsApp

• Despite call volume scaling significantly, NPS held steady during the highest volume months

Telefónica came to Wonderful looking for a vendor that could match what they already had, and ended up with an agent that outperforms it on every metric, serves their entire customer base, and has the rest of the organisation asking when they can get one too.