This might be a temporary solution but here is what worked for me:
Go into contents/Developer/platform/iPhoneOS.platform/DeviceSupport
Copy your previous iOS 14.5 the device support file or older version
Paste into the same folder and change the iOS number to 14.6
Restart Xcode, and it should let you run your code on your phone
FYI this has worked for me before too for a different iOS so it might be able to help for later versions if anyone gets stuck or cant run Xcode on their phone. Hope this helps!