SPen - funky functionality

so this is fun:

bought a new Note 5...
SPEN isn't working properly, when I remove the SPEN from the device, the device doesn't acknowledge it (regardless of whether the screen is on/off)

I rooted the device, thinking that a new rom might help, no luck

now, since it's rooted and KNOX is gone, I'm wondering what to do as far as getting a replacement


Does anyone have any tips?

Thanks!