You should start a new thread instead of responding to an 8 year old one. You got an issue with the app, but this is the web forum. It is probably unrelated to the watch model, but it is great that you mentions which one you got. The operating system of the phone is also interesting.
Try a restart of the phone. Check for updates of the app.
Post your issue in the a new thread in the correct forum and you will get help faster:
Android - https://forums.garmin.com/apps-software/mobile-apps-web/f/garmin-connect-mobile-andriod
iOS - https://forums.garmin.com/apps-software/mobile-apps-web/f/garmin-connect-mobile-ios