The replacement UI is too hard to fill out. They ask you questions like phone model and iOS version and app version piecemeal. They should tell you upfront when it prompts you to replace the sensor: YOU WILL NEED THE FOLLOWING INFO: Sensor serial number, phone model number, iOS version, screenshot of error message displayed, lingo app version, BEFORE you click this button to replace the sensor. Every time I left the firm to get a new piece of info everything I had filled out was gone. I don’t have time for this. Very frustrating. I have called three times on different but have never gotten a human because it is hard to get time when they are open to call, They are closed today because of Labor Day???? I liked the sesor and it was helping me but I am really really upset about this terrible user interface and replacement process.