Have you recently purchased the Chinese international Xiaomi Hey+ (Hey Plus) smart band? If so, you will be required to have a CHINESE phone number to unlock the software. Please note that the Hey+ is apparently manufactured by RYEEX, but is distributed by Xiaomi in China.
If you’ve bought the International version (as many other buyers have), the product will have everything in Chinese (packaging, documentation, Band firmware, companion phone app software, which is called Hey+ App).
When you run the companion phone app (called Hey+ App Hey Plus App), you are REQUIRED to enter a Chinese phone number to unlock the software. Once you input a China mobile phone number, they text you a SMS Verification code at that number, and you use the code to access the Hey+App.
The problem many people are running into is that You MUST enter a Chinese phone number. They have “hardcoded” the country prefix 86 (for China). It is impossible to enter your own phone number outside of China.
To obtain a temporary Chinese mobile phone number for Xiaomi Hey+ for verification, please use MobileSMS.io.