Hi and welcome to the forum,
Have you heard of the Dawn Phenomenon? Sometimes called a liver dump. When we wake in the mornings, not having eaten for 12 hours or so, our livers decide we need a bit of help to get our bodies moving, so it dumps glucose in our system to help with this. Some people are more prone to this than others, and this could be one reason why your fasting readings are higher.
Another reason might be the time you do your morning test. Ideally this should be immediately you get up and before you start to potter about, shower, make breakfast etc.
Another reason may be because your bedtime reading is high (do you take a bedtime reading?) If that is high then your fasting will be high as you are asleep and not burning a great deal of glucose. Try testing this if you don't already.
Other factors play a part, such as disturbed sleep.
Have a good read round the forums. There are plenty of posts about the Dawn Phenomenon if you type it in the search box.