Kibana discover does not display system index data

I have 1 index, it uses datastream, the name is .ds-xxx, currently the data can be written normally and query by GET request, but kibana discover does not show any data on this index, I created indext pattern when the system index is enabled, I in discover I also found the index pattern I created in that dropdown list, but after I select it, it doesn't show any data, the actual index has data

I found that when I create an index pattern in the 7.12.1 kibana version, the page displays the matching index with the datastream tag, but in discover, I can't find any data.

The above 2 are screenshots of my operation, I really do not see any problems

I eventually found out it was a time zone issue