Most sensors record a value every 15 minutes and not every 5. Freestyle libre 3 sensors should record it every 5 minutes!
For context: When data is available from a FreestyleLibre device, it will be streamed to you via webhooks. During your Terra account setup, you'll be prompted to provide a callback URL, allowing Terra to PUSH data using POST requests. The FreestyleLibre integration offers instant data delivery, eliminating the need for periodic requests.