Isn't it suddenly not connected?
Let's check the following points when Apple Watch, which had been used without any problems, "suddenly no longer connected to the iPhone".
● First, check the iPhone at hand
First, check if the paired iPhone is at hand.You may have forgotten it somewhere.
Open "Settings" and turn off "In -flight mode"
If there is an airplane icon on the dial, it is in the machine mode
If you swipe the Apple Watch screen from the bottom to the top, it will be the operation screen, so tap the airplane icon to turn off the in -flight mode.
If you have it, check "Is it powered?"Make sure that both the iPhone and the Apple Watch are not "in -flight mode", as you may have a missed operation mistake.After confirmation, both iPhone and Apple Watch are powered on, in-flight mode-off, Wi-Fi and Bluetooth on.
● Restart Apple Watch and iPhone
If you can't connect even if you need to connect, check if both the iPhone and the Apple Watch will be connected.
Since the iPhone X does not have a button for restart, turn it off completely and then turn on the power again.
The iPhone X keeps pressing the "side button and either volume adjustment button" and the "upper button (or side button)" before the slider is displayed before the iPhone 8 is displayed.Turn off the power completely.When the power is turned off, press the side button until the Apple logo is displayed.
Like the iPhone, turn off the Apple Watch restart.
The Apple Watch is turned off by pressing the side button (the right side of the main unit, the button below the Digital Crown) and slides "off the power" to the right.Press and hold the side button again to turn on the power.
● Unpaired the devices and pair again
If you have already been paired and you can't connect yet even after restarting your device, remove the pairing on both iPhone and Apple Watch, then pair again.
Start the "Watch" app and tap Apple Watch in pairing
Tap the "i" mark
Tap pairing
First, start the "Watch" app on the iPhone.Tap "My Watch" and display the paired Apple Watch, tap the "I" mark next to the name and tap "Unpairing with Apple Watch".
Tap "Settings" in Apple Watch
Tap "General"
Then, open "Settings" in Apple Watch and tap "General" → "Reset" → "Erase all content and settings".
Tap "Reset"
Tap "Erase all content and settings"
When the reset is completed, follow the instructions on the screen to pair Apple Watch and iPhone again.
* This article is Apple Watch Series 3 cellular model (WatchOS 4).3.1), iPhone X (iOS 11.4) Verification and created.