LG Stylo pen Doesn't open up When taken out

[Say-SayRosie]

My Lg Stylo4 pen does not open when I take the pen out and does not "Pop" or apps from pen does not show up
But When I put the pin back in it Pop up with the apps
But closes just as fast .( does not stay open ?
It is new never been dropped
Can someone please help
Thank you
S.S.Rosie.