Bring in to an Apple Store. They will look at it and even warrant it if it is defective.
The finger print activation has to have all of the print not just part of it. Go back into the settings and delete the print then do it again. Make sure the print goes completely RED and make sure there is no grey left.
I had to do this since I found the first time it just did not read my print correctly. I also used my first finger instead of my thumb.
It now works great turning the device on. Try it.
Good Luck
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