It is working as it is supposed too, so to speak. The graphs can not plot all the data in the size you show above, so it removes some of the data to be able to fit the graphic in the window provided. Sometimes this may even include your daily highs or lows such as in windspeed or temp. I have seen this happen in version 13 as well.
If you enlarge the graphs window or reduce the "Plot previous time" more of the data will again show up, because there is less data to display or more space to spread the data out across the window.