Slots (triggers/exits) have data types defined.
You can see the data type by selecting the slot and opening the rename dialog (it will appear as the Model Name) or checking the dataTypeId property (via Window>Show View>Properties).
Data types are either explicitly defined, or inferred via the flow arrows. If a slot with no data type is connected to a data element or to another slot with a data type defined, it will infer that data type "over" the flow.
<Done> exit slots have type Nothing pre-defined, and since the <Record> trigger of Insert has no predefined type it receives the same type. This is an error since Insert expects some Database Record-based structure (such as your NewItem).
The solution is simple. Just delete the <Done> exit and repolace with a regular exit (you can rename it if you wish). If you than check your data types you'll see that the new exit and the <Record> trigger types have changed to NewItem.
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