I'm wondering if the explanation for what you are experiencing is related to the two different platforms for Sentinel-2, namely S2A and S2B. There is some time between when one platform collects imagery for an area and when the other platform passes to collect that same area. On the Copernicus site, (Sentinel-2 - Missions - Resolution and Swath - Sentinel Handbook - Sentinel Online (copernicus.eu)) it reports, "Temporal resolution is the amount of time, expressed in days, that elapses before a satellite revisits a particular point on the Earth's surface. The satellites in the SENTINEL-2 constellation will provide a revisit time of 10 days at the equator with one satellite, and 5 days with 2 satellites under cloud-free conditions."
Do we know which platform (S2A or S2B) is being used to load data to the Sentinel services available on Living Atlas (Sentinel-2 Views and Sentinel-2 Level-2A)? Is it one, or the other, or both? I don't see that info reported.
To explore this idea, I checked the Copernicus site and verified an extent I am working in has S2A data with low cloud coverage that was collected on 25 Jul 2023, and in the same extent, there is S2B data with low cloud on 27 Jul 2023.
If I setup a DefQ "AcqusitionDate after 25 Jul 2023 and AcquisitionDate before 30 Jul 2023" on Sentinel-2 Level-2A service and I get data displayed for an extent I am working in (same data shown on the Copernicus site for the S2B platform on 27 Jul 2023). If I do the same query on Sentinel-2 Views service, I get no data displayed.
Next, I setup a DefQ on Sentinel-2 Level-2A service with a narrower window ("AcqusitionDate after 26 Jul 2023 and AcquisitionDate before 28 Jul 2023" and the same data is displayed as that on the Copernicus site for S2B on 27 Jul 2023. On Sentinel-2 Views service I edited the query to "AcqusitionDate after 24 Jul 2023 and AcquisitionDate before 26 Jul 2023"). The data that is displayed matches that on the Copernicus site for S2A on 25 Jul 2023.
You may want to look at both the Sentinel-2 Level-2A and Sentinel-2 Views services to see if either one may have the data you are looking for.