To reply to this discussion in order to close it correctly:

I have received an email from RIPE NCC Support who suggested me to send an email to top hostmaster@lacnic.net

I think that's what I'm going to do.

My purpose is not only to report spam abuse, but also to make sure that every ISP are doing their job correctly and comply to standard.

Thanks to everyone who has replied to my email :)

Happy New Year, by the way

On Fri, Aug 17, 2018 at 7:38 AM John Levine <johnl@iecc.com> wrote:
In article <alpine.LRH.2.21.1808162156240.1022@gauntlet.corp.fccn.pt> you write:
>> One of them is gestionip@TELEFONICA.NET.PE (because my company has received many many spams originated from its network so I wrote a spam
>complaint to this e-address but the mail was rejected for non-existent mailbox!)

My notes at abuse.net suggest these two addressses:

abuse@telefonica.com.pe (for telefonica.net.pe)
teris@tp.com.pe (for telefonica.net.pe)