C# : The instance of entity type 'Item' cannot be tracked because another instance with the same key

C# : The instance of entity type 'Item' cannot be tracked because another instance with the same key value for {'Id'} is already being tracked
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C# : The instance of entity type 'Item' cannot be tracked because another instance with the same key value for {'Id'} is already being tracked
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entity instance be value is already because the same type of for 'Item' with The {'Id'} C# : another tracked being key cannot tracked instance