Thank you for reaching out. I can certainly understand your frustration with your Galaxy watch 4 classic repeatedly disconnecting and I would be happy to look into this further for you.
The first troubleshooting step I would recommend trying is to clear the cache for the Galaxy wearables app and the Galaxy watch 4 Plug-In. Clearing App Cache removes all the temporary stored files the application uses when you open it next time. Go to settings > apps > tap the 3 dots in the top right corner > tap on show system apps > tap on each app individually > tap on force stop > tap on storage then clear cache.
Next step would be to reset the network connection on your device. Please know this will remove all saved Bluetooth and Wi-Fi connections saved on your device.
Third step to try would be uninstalling and re-installing the Galaxy wearables app on your device. This will allow you to have a fresh copy of the latest update available for your phone.
If you have tried all the troubleshooting provided, the final step before service would be to reset your watch. When you reset your watch, all of your personal data will be removed and the watch will restore back to its default settings, so you won't have to worry about personal info still being on it. You can reset your watch using the Settings or Reboot mode on the watch, or with the Galaxy Wearable app on your phone.
Note: Available screens and settings may vary by wireless service provider, software version, phone, or watch. When you reset a LTE watch that has active service, you may need to contact your service provider to reactivate service for the watch again. Give this link a try to assist with resetting your watch: https://www.samsung.com/us/support/answer/ANS00084702/
If you have tried all the troubleshooting steps and are still experiencing these symptoms, I would recommend a service repair.
You can use the following link to find a list of service centers in the U.S. that can do the repair:http://www.samsung.com/us/support/service/locationor by contacting customer support at 1-800-726-7864.
