I've do the following
curl -s https://packagecloud.io/install/repositories/phalcon/stable/script.deb.sh
Its says ok
Detected operating system as Ubuntu/focal.
Checking for curl...
Detected curl...
Checking for gpg...
Detected gpg...
Running apt-get update... done.
Installing apt-transport-https... done.
Installing /etc/apt/sources.list.d/phalcon_stable.list...done.
Importing packagecloud gpg key... done.
Running apt-get update... done.
But
[email protected]:~# apt-cache search phalcon
[email protected]:~# apt-get install php-phalcon
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package php-phalcon
It can't fetch the package! neithor apt-get install php7.4-phalcon
nor apt-get install php7.2-phalcon