Hi,
I recall a similar issue, it was related to ECS custom posts widget or something similar, see the discussion here. Some of the ticket is private, but basically they raised an issue with the developer here, some others have also reported the problem. Unfortunately they could not find the issue, but it had to do something with WP 6.0, reverting to 5.9 resolved the problem.
If you happen to use ECS or any custom post addon, then it is very likely the cause of the problem here. Unfortunately we can’t guarantee support for 3rd party Elementor addons. Switching to the original posts widget should resolve the problem. The search definitely does not return duplicates, it can’t because the query is distinctive by post IDs. When I debugged the upper mentioned ticket, I found that the plugin actually returned the correct items, simply the posts widget decided to display the first one 2 times – in your case the first 2.
I also remember another topic (I could not find it), where stickied posts caused this issue. You can check if these items by any chance sticked, maybe that also affect the duplication.
Also try different widget configurations, check if there is any custom query enabled, anything with sticky posts, extra meta queries or anything like that.