ERROR : This app was built with the iOS 12.0 SDK. Starting March 2019, all iOS apps submitted to the App Store must be built with the iOS 12.1 SDK

I get this ERROR that's preventing me from uploading to the AppStore

ERROR ITMS-90725: "SDK Version Issue. 

This app was built with the iOS 12.0 SDK. 

All iOS apps submitted to the App Store must be built with the iOS 12.1 SDK or later, included in Xcode 10.1 or later."

I don't have two xcode versions in my mac
I checked xcodebuild -sdk -version and I have 12.1 and I checked command line tools path by using "sudo xcode-select -s /Applications/Xcode.app/Contents/Developer"

Output of xcodebuild -sdk -version:

iPhoneOS12.1.sdk - iOS 12.1 (iphoneos12.1)
    SDKVersion: 12.1
    Path: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS12.1.sdk
    PlatformVersion: 12.1
    PlatformPath: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform
    BuildID: ...
    ProductBuildVersion: 16B91
    ProductCopyright: 1983-2018 Apple Inc.
    ProductName: iPhone OS
    ProductVersion: 12.1

    iPhoneSimulator12.1.sdk - Simulator - iOS 12.1 (iphonesimulator12.1)
    SDKVersion: 12.1
    Path: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator12.1.sdk
    PlatformVersion: 12.1
    PlatformPath: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform
    BuildID: ...
    ProductBuildVersion: 16B91
    ProductCopyright: 1983-2018 Apple Inc.
    ProductName: iPhone OS
    ProductVersion: 12.1

    MacOSX10.14.sdk - macOS 10.14 (macosx10.14)
    SDKVersion: 10.14
    Path: /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk
    PlatformVersion: 1.1
    PlatformPath: /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform
    ProductBuildVersion: 18B71
    ProductCopyright: 1983-2018 Apple Inc.
    ProductName: Mac OS X
    ProductUserVisibleVersion: 10.14.1
    ProductVersion: 10.14.1

    AppleTVOS12.1.sdk - tvOS 12.1 (appletvos12.1)
    SDKVersion: 12.1
    Path: /Applications/Xcode.app/Contents/Developer/Platforms/AppleTVOS.platform/Developer/SDKs/AppleTVOS12.1.sdk
    PlatformVersion: 12.1
    PlatformPath: /Applications/Xcode.app/Contents/Developer/Platforms/AppleTVOS.platform
    BuildID: ...
    ProductBuildVersion: 16J602
    ProductCopyright: 1983-2018 Apple Inc.
    ProductName: Apple TVOS
    ProductVersion: 12.1

    AppleTVSimulator12.1.sdk - Simulator - tvOS 12.1 (appletvsimulator12.1)
    SDKVersion: 12.1
    Path: /Applications/Xcode.app/Contents/Developer/Platforms/AppleTVSimulator.platform/Developer/SDKs/AppleTVSimulator12.1.sdk
    PlatformVersion: 12.1
    PlatformPath: /Applications/Xcode.app/Contents/Developer/Platforms/AppleTVSimulator.platform
    BuildID: ...
    ProductBuildVersion: 16J602
    ProductCopyright: 1983-2018 Apple Inc.
    ProductName: Apple TVOS
    ProductVersion: 12.1

    WatchOS5.1.sdk - watchOS 5.1 (watchos5.1)
    SDKVersion: 5.1
    Path: /Applications/Xcode.app/Contents/Developer/Platforms/WatchOS.platform/Developer/SDKs/WatchOS5.1.sdk
    PlatformVersion: 5.1
    PlatformPath: /Applications/Xcode.app/Contents/Developer/Platforms/WatchOS.platform
    BuildID: ...
    ProductBuildVersion: 16R591
    ProductCopyright: 1983-2018 Apple Inc.
    ProductName: Watch OS
    ProductVersion: 5.1

    WatchSimulator5.1.sdk - Simulator - watchOS 5.1 (watchsimulator5.1)
    SDKVersion: 5.1
    Path: /Applications/Xcode.app/Contents/Developer/Platforms/WatchSimulator.platform/Developer/SDKs/WatchSimulator5.1.sdk
    PlatformVersion: 5.1
    PlatformPath: /Applications/Xcode.app/Contents/Developer/Platforms/WatchSimulator.platform
    BuildID: ...
    ProductBuildVersion: 16R591
    ProductCopyright: 1983-2018 Apple Inc.
    ProductName: Watch OS
    ProductVersion: 5.1

    Xcode 10.1
    Build version 10B61

I have base sdk set to iOS in my build settings
I use xcode 10.1 (10B61)
I uninstalled and reinstalled Xcode

Any ideas? I can't upload to the AppStore anymore, it's been a week now of searching for a solution, I can't find the solution.

Solution

Apparently, in Xcode 10.2 this problem doesen't exist. After trying numerous solutions, the one that did it for me was Installing the 10.2 version of Xcode. I hope this answer can help someone save some time.