W: GPG error: http://debian.neo4j.org/repo stable/ Release: The following signatures were invalid: BADSIG 26C95CF201182252 Neo Technology Admins <admins@neotechnology.com>
E: The repository 'http://debian.neo4j.org/repo stable/ Release' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: Target Packages (Packages) is configured multiple times in /etc/apt/sources.list.d/neo4j.list:1 and /etc/apt/sources.list.d/neo4j.list:2
W: Target Translations (en) is configured multiple times in /etc/apt/sources.list.d/neo4j.list:1 and /etc/apt/sources.list.d/neo4j.list:2
I don't know what instructions you were following, but we've never had a repository at Neo4j Debian Packages
You should delete that from your sources lists. You already have the correct one set up at debian.neo4j.com