PLANEO Elektro's BigHub Voicebot on ElevenLabs and Azure OpenAI Resolves 52% of the Calls It Takes End to End

PLANEO Elektro (FAST ČR, a.s.), one of the largest Czech consumer-electronics retailers with more than a hundred stores and an e-shop, has deployed a voice AI assistant built by BigHub on its customer phone line, according to a BigHub case study. Many of the hundreds of daily calls ask the same things: where an order is, extending a pickup, resending an invoice, a failed card payment or cancelling an order. The aim was not to cut agent costs but to stop customers waiting for information the system already holds, and to leave agents free for complaints and service cases. The project took three months and built on DIEGO, an internal AI assistant for store staff that PLANEO had launched with BigHub a year earlier; the Azure AI Search knowledge base behind DIEGO also supplies the voicebot's answers, which lowered the cost of the second project. Callers describe their request in their own words, the system recognises the intent and passes it to a specialised agent, built on a LangGraph multi-agent architecture, that can act in SAP, for example extending an in-store reservation, cancelling an order or resending an invoice. Complex requests, or callers who ask for a person, are handed to an agent together with what the voicebot has already gathered. The voice layer uses ElevenLabs Conversational AI with OpenAI models in Azure, chosen for low latency, and supports barge-in so callers can interrupt, with a Czech voice that handles declension and order numbers. Calls arrive through a SIP server that PLANEO's phone exchange redirects to, and the solution runs in PLANEO's own Azure environment using Azure Container Apps, CosmosDB for PostgreSQL and Azure Key Vault. In production, 4,378 calls entered the voicebot and 52% were resolved end to end with no agent, while 2,101 were handed to an agent; the average voicebot call lasted 2 minutes 58 seconds. Of all calls, 1.6% were abandoned during the voicebot conversation and 5.8% while waiting for an agent after handoff, so roughly four in five lost calls came during the wait. Lukáš Daněk, Head of Customer Care, said that in the first month of production the voicebot "resolved 53% of all 12,600 incoming calls entirely on its own." Planned next steps include a Slovak version and a text assistant on planeo.cz.