Could you please confirm that this is the markup you really use. I doubt that this will work with these relations settings because as stated in out online documentation: "You must set the DataKeyNames property of every parent table view in the hierarchy to specify the fields in the table's data source that are used for linking to child tables."
Also which version of the controls do you use? We are not familiar with such an issue.
It will be best if you open a regular support ticket and send us a project that successfully reproduces the problem so we can test and debug locally. With this current snipped the issue is not reproducing event I correct the table relations.
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