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Thank you for reporting this and sharing the screenshot. I can see the People heading overlapping the Moments navigation item. Could you share your Windows version and build? You can find them by pressing Windows + R, typing winver, and pressing Enter. Also, what Photos app version is shown under its settings, if available, and what Scale and Display resolution are listed under Settings > System > Display?
As a test, please maximize the Photos window, then restore and resize it to see whether the overlap changes. If it persists, note your current display scale and temporarily try a different scale under Settings > System > Display, then reopen Photos; you can switch back afterward. Please let me know whether either test changes the layout.