QBO is allowing me to double enter a bill. is there a setting so it will not allow this to happen?

You can use the Search bar at the top of any page, here in the community, to find answers to most questions.  In doing so, I was able to find you a thread that best answers your question.  

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https://quickbooks.intuit.com/learn-support/en-us/reports-and-accounting/is-there-an-alert-in-qbo-to...

Thank you, that's exactly what i was looking for... problem solved!