On my 2015 S which is gas the oil indicator only reads after 6 miles after the hood is opened. To check again open hood and close it. Drive for 6 miles or so to get a new reading.
After I changed oil I kept adding and driving until it was right. Normally the system averages the oil level over time and only changes the reading after it has determined the oil level has really moved a level mark for sure. The engines have plenty of oil so don't get the owners all wound up about little changes.

 

got it thanks, just need some oil, its hard to get from auto parts stores

 

Only had this issue after one oil change. On the third visit asked the dealer to let me see the oil level on the Porsche dip stick that is a maintenance tool. Found out they did not have the Porsche tool. After borrowing the tool from an Audi dealer the level was in fact low. When serviced using the dip stick the bars indicated full. The Porsche maintenance dip stick has an adjustable stop for various model cars. We are using a different dealer now!