[SOLVED] Google search console error regarding "name"

For our detail page based on JEM Simplelist page Google search console stated an error: Critical problem - Field "name" is missing. 

That is related to structured data. The field is missing in the event markup. This is considered critical because without it, Google cannot display the event properly in search results.

The event page has several tags "itemprop" for startdate, url to provide the structured data but the name is missing at top level (although it is at the venue-id1 level)

Is that an issue of my installation? my settings? 

Installation: Newest joomla 5.4, jem 4.3.4 and php 8.4, using JEM Simpelist for the details page. 
 

Hello hklages,
JEM 4.3.4 actuallz does have valid microdata in the simple list and also on the event detail pages.
You may be using template overrides where the microdata is not fully implemented. If you are using template overrides, please disable them for testing with the Google Rich Data Checker: search.google.com/test/rich-results
If the error persists, please let us know so we can take a closer look.

Edith: you can also use the schema validator validator.schema.org/

Neither for Cassiopia nor for Purity iv template there are any "jem overrides".  The JEM Simplelist is bind to a menu item with Casseiopia template. 

I checked the event details with scheme validator and it shows url, description, startDate but not the name for that event. 

Installation is as follows for the webside pcagev at top level domain de: 
veranstaltungen: menu item with template purity iv business - article - JEM module teaser  ->> everyhing ok
but when clicking on the title the details page open and there is the issue

event-details: hidden menu item with template casseiopia - JEM Singlelist  ->> everythink ok
but when clicking on the title the details page opens and there is the issue. 
 

@Hehla I have checked and Google doesn't see the any microdata.
Send you a PM.

For my personal test page (J5 and JEM 4.3.4), www.j4.datenablage.info Google tells me, that the microdata is valid:
search.google.com/test/rich-results/result/r%2Fevents?id=kUVu-uTfoOOj2zgMoW7c2g
the same here:
validator.schema.org/#url=https%3A%2F%2Fwww.j4.datenablage.info

@hklages could you send my the URL of your site (hier or PM)

I could identify the problem:
In the JEM settings if you have "Display Event Title" on "no" in the "event page" then the micro data is disabled as well.
I check it out and will provide a solution.