If you have an Android device, Automatic Updates should automatically be turned on. If your pass has not updated try turning your phone off and on again to update your pass, alternatively you can remove the pass from your wallet and download it again via the Arsenal App.
If your digital pass still hasn't updated to show the next game, but instead is showing a previous game or is showing no seat details, don’t worry! Simply click on the "Show Code" option, and a barcode will appear. Rest assured you can use that barcode to gain entry to the stadium.