Your question has already been answered in the support thread you have opened on the same topic. However, I am posting the answer here as well in order the community to benefit from it.
According to the provided information, it would be difficult to conclude what causes the hierarchy to disappear since I am not familiar with the complete hierarchy setup on your end. There are no specific properties that are compatible or not with hoerarchy.
However, I would like to mention what is important to build an hierarchy:
1. Populate data on the master level.
2. Add a child GridViewTemplate and populate it with some data. Please make sure that there is a filed from the child level that points to the respective parent record, e.g. ParentId in the child template and Id in the master template.
3. Define a relation between the two templates and specify the columns that build the relation (ParentId and Id).
If some of the above mentioned steps is not accomplished, the hierarchy won't be built properly.
You can refer to the Hierarchical Grid in Unbound mode section in the following help article for more details: https://docs.telerik.com/devtools/winforms/controls/gridview/hierarchical-grid/binding-to-hierarchical-data-programmatically
We kindly ask you to use just one thread for a specific problem to contact us. Posting the same questions numerous times slows down our response time because we will need to review and address two or more tickets instead of one. Moreover, threads are handled according to license and time of posting, so if it is an urgent problem, we suggest you use a support ticket, which would be handled before a forum thread.
Thank you for your understanding.
Dess | Tech Support Engineer, Sr.
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