Unable to factory reset

Hi to all.

I need your help!
I have a Samsung Galaxy Note 8.0 GT-N5110 that don't boot (it is stock in the Samsung logo)

And I can't enter the factory reset menu.

If a Press & hold [Vol-] + [Power] I get a screen that says:
Warning!!
A custom OS can cause critical problems
in phone and installed applications.

If you want to download a custom OS,
press the volume up key.
Otherwise, press the volume down key
to cancel.

Volume up: Continue
Volume down: Cancel 8restart phone)

If I Press [Vol+] + [Power] I get a screen that says:

Downloading...
Do not turn off target !!

If I Press [Vol+] + [Home] + [Power] I get the same screen that before:

Downloading...
Do not turn off target !!

Any help will be appreciated.