a case record is by default created associating your current logged user (contact) with the customer field under the case record
if you want to create an additional record you can use the option "Create Related Record" in your entity form, with…
This needs a tweak in Organization level. Follow the step in this blog to get it resolved.
You create the plugin and register 2 steps on it.
1) for the update - set the message to update, the primary entity to your entity and add the field to the filter attributes and it will run automatically if the field is updated.
2) for the create - set…
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