If you don’t see the version you need listed in the build dropdown:
Go to Settings > Components and select + button at the bottom, and download the one you need:
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If after a successful download, you still don’t see this version listed here:
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It’s either one of two things:
- Try selecting earlier versions of “Device Type” before checking the “OS Version”. Some earlier OS versions are not supported on the latest device
- If that doesn’t work restar your computer. Sometimes Xcode doesn’t detect newly installed simulators.