Error Trying to Install iOS 18.0 in Xcode 16(16A242d)

Ussing XCodes I am trying to install the iOS 18.0 Platform in Xcode 16(16A242d). I am getting the error : "Unable to Install Xcode Invalid runtime source" I am a complete mac newbie. I am using (hoping to use) .net MAUI to build an app that i have created in windows for Andriod. Any help would be much appreciated.

I am using Sequoia 15.0.1

Error Trying to Install iOS 18.0 in Xcode 16(16A242d)
 
 
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