Installing Android 8.1 has led to problems swiping on the Pixel 2/2 XL and certain Nexus models17
According to the threads that have been posted, it can take multiple attempts at swiping before the handset figures out that you want to enter your PIN code to unlock it. Notifications on the lock screen can also take multiple swipe attempts to get rid of. Accepting or declining incoming phone calls can also become a chore thanks to this bug.
This is an example of what is so maddening about the Pixel 2 and Pixel 2 XL. Specs-wise and design-wise these handsets should both be among the best Android phones of 2017. But issues with the screen, speakers and swiping are frustrating users. Google is said to be looking into the matter. Since a software update apparently brought on this problem, you would think that another update is all that would be required to fix it. If we hear anything new about this bug, we will pass it along to you.
source: GoogleSupport, Reddit via AndroidCentral