An electronic device and method are disclosed herein. The electronic device implements the method, including: receiving a first speech, and extracting a first text from the received first speech, in response to detecting that extraction of the first text includes errors such that a request associated with the first speech is unprocessable, storing the extracted first text, receiving a second speech and extracting a second text from the received second speech, in response to detecting that the request is processable using the extracted second text, detecting whether a similarity between the first and second texts is greater than a similarity threshold, and whether the second speech is received within a predetermined time duration of receiving the first speech, and when the similarity is greater than the threshold, and the first and second speech signals are received within the time duration, storing the first text in association with the second text.