I got a galaxy 4 watch last week and it won't count steps or measure heart rate etc. I have tried several solutions that have been posted and am still not able to get it to work.
you can reproduce the issue then report to samsung using Wearable app > menu > contact us > error report
or you can also visit authorized repair center for hardware checkup
Hello, I understand how frustrating this must have been. If the step and heart rate tracking features are not working properly on your watch, the watch band or strap may be too loose or the watch's software might need updating. I am including a link to a guide to assist you with your concerns https://www.samsung.com/us/support/troubleshooting/TSG01003204/.