Solution for Apple Watch which doesn't upgrade nor pair

I just bought a brand new Apple Watch Series 4 from Amazon as they recently got great discount. However, the Apple Watch cannot pair with my iPhone Pro 11, iOS 13.2.3. Every time I try to pair the watch with my phone it just stuck at the "We are connecting your Apple Watch with your iPhone, etc", like forever. I was trying to upgrade the Apple Watch but also without any success as it complains there is no internet connection.

I believe a lot of people are experiencing the same issue as me lately. This forum are filled with similar posts and the only suggestion we can get is reset the watch or phone. Trust me, non of them works. It's the issue with Apple's service. Nothing is wrong with your Apple Watch or your iPhone! I spent 1 day to resolve this issue and finically found a solution so I'm gonna share it with people who are also sick of the useless suggestions.

I guess something went wrong with the newest iOS and maybe the WatchOS of the Apple Watch isn't compatible with it. Fortunately I got a spare iPhone 6 which still stays at iOS 12.2. The rest of the solution are pretty simple then. Pair and set up the Watch with iPhone 6. Check for update. Detect Watch OS 5.3.3 is available. Successfully download and install the 5.3.3 WatchOS. Unpair it with iPhone 6. Pair it with iPhone Pro 11. Everything just works fine as it was supposed to be. Here is the time I actually spent on upgrading the Apple Watch.

Took 3 and half hours to download the update to Apple Watch.

Took 4 minutes to prepare the upgrade.

Took 10 minutes to verify the upgrade.

Took 3 minutes to install the upgrade.

Pair it with the iPhone Pro 11. Finally! The terms and conditions page!! Then there was a page indicates that "Signing into your account. This may take a few minutes." instead of "We are connecting to your iPhone, etc". 2 minutes later the Apple Watch is good to go. For those guys who don't have old version iPhone/iOS. I think there is no other solution but waiting for Apple to roll out some updates to fix this issue. There is definitely nothing wrong with your hardware.