For anyone who encountered the same issue, can try with following steps:
Install sysdiagnose profile on iPhone: https://download.developer.apple.com/iOS/watchOS_Logs/sysdiagnose_Logging_Instructions.pdf
Trigger a sysdiagnose by pressing and holding both the Side and Digital Crown buttons on the Watch for two seconds and release, Watch will restart automatically
Restart Xcode and hopefully it may recognise the Watch
Topic:
Developer Tools & Services
SubTopic:
Xcode
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