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I recently purchased a fingertip pulse oximeter from Amazon, but unfortunately, the device is not functioning properly. After checking the battery, I found it to be okay, yet the screen remains blank, indicating a possible defect. As this device was intended for personal use, it's quite frustrating that it's not working as expected. I would like to request a return for a replacement as soon as possible. Please provide me with the necessary steps to initiate the return process. I appreciate your prompt attention to this matter and look forward to resolving this issue quickly. Thank you in advance for your assistance!