Null ReferenceException: Object reference not set to an instance of an object in RegrowableHarvestBehavior with ‘parentCrop.Regrow();’
Do a Debug.Log of parentCrop after the line with the error, you should find that the parentCrop object is null. That is what the NullReferenceException is highlighting.
You can check if the parentCrop is destroyed or missing on the Inspector as you are playing your game in the editor.
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