To resolve this, you have to go to the person that delegated their outlook and change the permissions. Uncheck where it says “Delegate receives copies of meeting-related messages sent to me”
To get there: Click File in Outlook: 
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Then Click on Account Settings.
Next Click Delegate Access:
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Next Double Click the user name, in Here it will show
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Then Uncheck where it says “Delegate receives copies of meeting-related messages sent to me”
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And then click Okay.