I have a new build in App Store Connect, however when I attempt to add a New Version, I get an error. It makes no difference which number I enter. Any ideas about the cause? Thanks

I’m getting in to iOS dev for the first time and am about to buy a Mac mini M2 but the 8GB is much cheaper than the 16GB so I’m wondering if that’s enough to start with. I can’t find an official spec for Xcode 14 and other posts are out of date. Thanks