How to unlock nexus 5X without deleting data on forgetting pin i forgot my pin to unlock the phone. Even after entering wrong pin 15 to 20 times, it kept on asking me to enter the pin after 30 seconds. But never prompted me if i have forgotten my pin. 
I tried restarting my phone and it went to airplane mode. And now, on entering wrong pin, it says "warning: your device will be wiped after 9 more failed attempts to be unlocked". 
Does anyone have any idea how to unlock without erasing my data. Please help.
android version after 4.4 does not ask user if they have forgot pin or password, not sure why will they do it, but unfortunately android have been  designed in such a secure way that they don't want anyone to have access to our data even though they breach into our device by whatsoever means, so there is no means you can have access to your data without a password or if there were a way someone else would also have been able to do the same.
If you are thinking about rooting unless its already bootloader unlocked your device is unable to be broken into for data