Hi.
My pump has been exchange because i was having trouble with the transmitter connexion and i receive a pump who hasn’t its history cleaned !!
I check over internet how to factory reset my “new” pump or clean the history but don’t find how to 
Help would be appreciated…
Reset steps/video (put in storage mode, then wake up).
I was on a call with tech one time, and this is what they instructed me to do, and fixed problem i was having.
Hi MM1.
As i receive a refurbished pump, it was in storage mode. I saw that history was filled…, i re do the “put in the storage mode”, and wake up once again, but history is always populated. 
I’m sorry, but you need to call customer service if you’re displeased. And I sure would be. I took every opportunity I had to get a refurbished pump when I was still in warranty, because it always felt like getting a brand new one. It was exciting. I feel like yours hasn’t actually been properly refurbished.
You should have a really valid argument for a replacement since this one taints your medical records, which your doctor uses to help you manage, and that historical data (especially TDD) influences Control-IQ behavior.
I don’t believe this is something that can be done yourself, not should you have to. It should be safe to use until they send you a proper refurb, though.
The history will keep at least 90 days then delete the oldest.
According my health support, there is no way to factory reset the pump, or to delete the history. 
I will not be easy for medical, and myself…