Samsung S6 lite fortunately comes with S pen but there is a issue regarding that.
The s pen when used regularly gets easily teardown(nib of spen)and it doesn't work properly. I don't if there is any replacement for the nib as whether you can purchase it from Amazon which is not same as original Spen nib. I request samsung care for any help regarding this issue.
We request you to kindly visit the service center for a physical inspection of your device. You can locate your nearest service center with this given link: https://www.samsung.com/in/support/service-center/
