Why Spen in note 3 not working well

[Haitham Hemdan]

I need your help, i have already samsung galaxy note 3 SM N9005 , it worked very well.
But,from yesterday i had a problem ,S pen not working suddenly,the phone detect attach and detatch the pen by sound and vibration,but no response to touch nor point marker during hover the pen on screen.
I tried to made reset factory and flash stock firmware again, but also the problem still existed.
I tried my pen in another note 3 ,working well with the another phone and the another pen not working with my phone
Help,plz

 

[Rukbat]

Most likely, the SPen layer of the screen has gone bad, or the parts on the motherboard that connect to that layer have gone bad. (The SPen isn't just a "plastic finger", there's an additional layer in the screen that makes it work.)

The phone has to go to a repair shop for troubleshooting and, if you want to spend the money, repair. (You may want to buy a good used phone if the repair will be more than the used phone.)

 

[Fulani Filot]

In addition to what Rukbat said, you can also do an SPen test by dialling the following USSD code:
*#0*#
This will launch a service menu that looks like the one pictured. Tap the circled (in magenta) option and do the test.