@Alex-Gascón the watch you have has very little memory, so you may need to make some space by removing guides that you do not use, to load the ones you want to use.

@Shlomo-Sackstein maybe a calibration error. Try depleting the watch and then charge it for a couple of hours. I that doesn’t help, contact support

Short Information: a restart of the Samsung mobile has been solved the problem. This was the only thing which wasn‘t done before I opened this post. Thanks, Dirk