Solved! Back button issues

[Alexandrugsx]

Samsung Grand Prime G531F issues: the back and menu buttons doesn't work or work random.
The rest of touchscreen work very well. Only this 2 buttons work random or aren't work at all.
I don't know what to do.
Please help me because is very annoying.

 

[Graybush]

Have you tried a soft restart on the phone? Sometimes the responsiveness on tablets and phone are a result of a software issue.

 

[Alexandrugsx]

No i didnt try that. I am not sure how to perform soft or hard restart or reset. I am not familiar with this kind of action on my phone.
If anyone tells me how to do it i will try.

PS: please excuse my bad english, i'm from a non speaking english country.

 

[Graybush]

On Samsung phones, a soft reset can be selected by holding down the power button, and then selecting 'restart' from the shut down selections on the phone.

A hard restart, from my understanding, is to also hold down the power button, but then you select 'shut down' and let the phone turn itself off. Wait 10-15 seconds, then press the power button to turn the phone back on.

 

[Alexandrugsx]

I allready did this two operations.
I think its need a hard full reset with backups and all clean old settings. But i dont know how to do it.
Right now my back button is working fine. As i said work bad random.

 

[Graybush]

You can try doing a factory reset, but I would make sure to back up any information you have before doing so.