Hi seitinemam,
If you haven't done so yet, restart your Apple Watch and iPhone. Although simple, this step can help correct some unexpected issues. It's also a good idea to make sure both devices are running the latest software versions, since this can help with overall performance. If an update is available for your iPhone, be sure to create a backup before installing it.
Update your iPhone or iPad
1. Back up your device using iCloud or your computer.
2. Plug your device into power and connect to the internet with Wi-Fi.
3. Go to Settings > General, then tap Software Update.
4. If you see more than one software update option available, choose the one that you want to install.
5. Tap Install Now. If you see Download and Install instead, tap it to download the update, enter your passcode, then tap Install Now. If you don't know your passcode, learn what to do.
Update your Apple Watch
If the issue persists, reach out to Apple Support directly so they can look into this with you further. They can be contacted here: Get Support or by calling the most applicable phone number from this list: Contact Apple for support and service.
Regards.