I have recently been able to run AutoML successfully on a certain dataset.  But it has just failed on a second dataset of similar construction, before being able to produce any machine learning training runs or output.  The Experiments page says

```Model training failed
For more information, visit the AutoML job run. 
An unknown error occurred```

The phrase "AutoML job run" links to a Run of an auto-generated training notebook.  In that notebook, the failure occurs in a cell whose contents are :

The error statement is `A column, variable, or function parameter with name `_automl_sample_weight_0000` cannot be resolved.`.  That name `_automl_sample_weight_0000` is, of course, not from my data - it's something that AutoML is creating, or failing to create.

I am not using Feature Store or anything super-clever in the ML pipeline.  My data simply comes from a Delta Table, albeit a bigger one than when the AutoML worked successfully for me.  Call this one 50000 rows by 6000 columns.

Any suggestions for repairing?