Google Groups are reserved for general product discussion, StackOverflow for technical questions whereas Issue Tracker for product issues (unexpected behaviors) and feature requests, see [1].
For this reason, since the behavior you described (an internal error) is unexpected, I strongly suggest opening an issue with issue-tracker [2], where you may get updates from the product team, if needed, regarding this issue. Nonetheless, please make sure first that your training dataset complies to the requirements in [3], otherwise; this may be a potential reason for an internal error
Best regards.
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