Why the list created by means of ipset is not saved?

Question

iptables

Followed instructions for Blocking IP addresses in Linux with iptables .
Checked:
ipset list blacklist
All the rules, I go on the trail. I check the day again and for some reason it's empty there. Issues:

ipset v6.20.1: The set with the given name does not exist

Even tried to do, but does not help:
ipset save blacklist

Answer 1

I follow the trail. day

Where is this "going"? Have you restarted your computer? In this case, you must do iptables-save > rules.txt before reloading, and restore after loading: cat rules.txt | iptables restore.
Optionally, instead, you can raise the rules through rc.local or, more civilized, through a post-up script from /etc/network/interfaces.