Hello, and thanks for your feedback on the MEATER Pro Duo. Often times when it appears that the cook estimator is not working, it may actually just be delayed. This can occur for a few different reasons, such as having the probe in very cold meats, slow warm up time of the grill, or constant changes to the cooking appliance’s temperature setting. While this may substantially extend the initial estimate calculation, it'll eventually be provided once the probes reading increases by approximately 16°F/8°C. However, if you believe that this is not the case in your situation, or would just like some help finding out for sure, please reach out to MEATER Customer Service through the contact information available at support.meater.com/contact-us, and one of our agents will be happy to check everything with you to see what needs to be done to get your cook estimates updating as they should be.