Unable to build watchOS app on Apple Watch via Xcode

I am unable to install my watch app on my Apple Watch via Xcode. There is no code change from my end and this issue just happened recently. My Apple Watch is running on watchOS 7.3. This is the error log I received whenever I tried to build my watchOS app.

Code Block 
Details
Unable to install "xxxxx Watch App"
Domain: com.apple.dt.MobileDeviceErrorDomain
Code: -402652944
--
The version of WatchKit used by this app is no longer supported on this version of watchOS.
Domain: com.apple.dt.MobileDeviceErrorDomain
Code: -402652944
User Info: {
    DVTRadarComponentKey = 261622;
    MobileDeviceErrorCode = "(0xE80000F0)";
    "com.apple.dtdevicekit.stacktrace" = (
	0   DTDeviceKitBase                     0x000000012e633c8f DTDKCreateNSErrorFromAMDErrorCode + 220
	1   DTDeviceKitBase                     0x000000012e672241 90-[DTDKMobileDeviceToken installApplicationBundleAtPath:withOptions:andError:withCallback:]_block_invoke + 155
	2   DVTFoundation                       0x000000010b53e64b DVTInvokeWithStrongOwnership + 71
	3   DTDeviceKitBase                     0x000000012e671f82 -[DTDKMobileDeviceToken installApplicationBundleAtPath:withOptions:andError:withCallback:] + 1440
	4   IDEiOSSupportCore                   0x000000012e4e2a10 118-[DVTiOSDevice(DVTiPhoneApplicationInstallation) processAppInstallSet:appUninstallSet:installOptions:completionBlock:]_block_invoke.292 + 3513
	5   DVTFoundation                       0x000000010b66d17e DVT_CALLING_CLIENT_BLOCK + 7
	6   DVTFoundation                       0x000000010b66eda0 __DVTDispatchAsync_block_invoke + 1191
	7   libdispatch.dylib                   0x00007fff2018b5dd _dispatch_call_block_and_release + 12
	8   libdispatch.dylib                   0x00007fff2018c7c7 _dispatch_client_callout + 8
	9   libdispatch.dylib                   0x00007fff201925fe _dispatch_lane_serial_drain + 606
	10  libdispatch.dylib                   0x00007fff201930cb _dispatch_lane_invoke + 375
	11  libdispatch.dylib                   0x00007fff2019cc5d _dispatch_workloop_worker_thread + 819
	12  libsystem_pthread.dylib             0x00007fff20334499 _pthread_wqthread + 314
	13  libsystem_pthread.dylib             0x00007fff20333467 start_wqthread + 15
);
}
--
System Information
macOS Version 11.2 (Build 20D64)
Xcode 12.4 (17801) (Build 12D4e)
Timestamp: 2021-02-04T00:36:31+08:00

Things I have tried:

1. Upgrading/downgrading Xcode (version 12.2, 12.3, 12.4 and 12.5 beta)

2. Deleting "Derived Data" folders

3. Unpairing/Pairing my Apple Watch

4. Cleaning the project and restarting XCode

Any help would be greatly appreciated. Thank you!