How to Fix "This iPhone xx is running iOS 13.3.1 (17D50), which may not be supported by this version of Xcode."

13.3.1 = iOS version number
(17D50) = build number

Solutions:

• Step 1: Download iOS version 13.3.1 (17D50) from github
• Step 2: Unzip downloaded file
• Step 3: Close Xcode
• Step 4: Go to Application Folder and Find Xcode;
• Step 5: Right click on Xcode and click on "Show Package Content";
• Step 6: Then, go to Contents -> Developer -> Platforms -> iPhoneOS.platforms -> DeviceSupport
• Step 7: Now, drag and drop the updates device support file to the old Xcode Device support folder and restart the Xcode. This should have fixed the error

Device Support files for Xcode

• iPhoneOS
• AppleTVOS
• WatchOS