I have recently made a book assessable through KDP and Amazon. I have been told that Kindle readers have gotten the books but the reports show 0 activity when I check reports. Any information or suggestions are appreciated. Thank you.
Assuming you mean accessible, and not assessable, there are two separate issues relating to reported sales.
Paperbacks generally take longer to come through, as they're not recorded until after shipping, and an oft made mistake is that they've been published through Create Space, but the publisher is expecting to see the sales on the KDP pages. If that's what happened, you need to check your Create Space dashboard instead.
For e-books, there is often a lag of up to a day, but rarely more.
So, that probably brings us to the heart of the problem. Who told you they'd bought your book?
To quote one of our more colourful peers, who has today announced his retirement from the forums (I'm still in mourning), if it was a friend, they probably lied to get you off their back. If it was a family member, they too probably lied to get you off their back. That's what friends and family do, to stop you badgering them to buy your book. They don't realise that when you have zero sales, it's pretty easy to figure out when they're lying.
So you have two choices when that happens. You can either smile and say thank you and chalk it up to experience, or you can complain to the 'zon about your missing sales, only to have them reply that there is no 'systematic failure in their reporting systems'. Welcome to the world of publishing!
I hope it's the first one (paperbacks on CS) but either way, I hope you figure it out soon.