NextcloudPi Update to v1.3 not possible

Nextcloud version (eg, 18.0.2) : 18.0.7.1
Operating system and version (eg, Ubuntu 20.04) : Debian GNU/Linux 10 \n \l
Apache or nginx version (eg, Apache 2.4.25) : 2.4.38
PHP version (eg, 7.1) : 7.3.19-1
NextCloudPlus: v 1.28.1

When Updating to NextCloudPlus, I get the following error messages:

version v1.30.0 is available

Update NextCloudPi

[ nc-update ] (Mon Sep 21 09:28:45 CEST 2020)
Downloading updates
Performing updates
Hit:1 http://packages.x2go.org/debian buster InRelease
Hit:2 http://security.debian.org/debian-security buster/updates InRelease
Hit:3 http://deb.debian.org/debian buster InRelease
Hit:4 http://deb.debian.org/debian buster-updates InRelease
Hit:5 http://dl.google.com/linux/chrome/deb stable InRelease
Hit:6 https://deb.nodesource.com/node_10.x buster InRelease
Get:7 http://ppa.launchpad.net/jtaylor/keepass/ubuntu focal InRelease [17.5 kB]
Get:8 http://ppa.launchpad.net/snappy-dev/image/ubuntu focal InRelease [18.1 kB]
Get:9 http://ppa.launchpad.net/yktooo/ppa/ubuntu focal InRelease [17.5 kB]
Err:7 http://ppa.launchpad.net/jtaylor/keepass/ubuntu focal InRelease
The following signatures couldnā€™t be verified because the public key is not available: NO_PUBKEY 7858088158B80F90
Err:8 http://ppa.launchpad.net/snappy-dev/image/ubuntu focal InRelease
The following signatures couldnā€™t be verified because the public key is not available: NO_PUBKEY F1831DDAFC42E99D
Err:9 http://ppa.launchpad.net/yktooo/ppa/ubuntu focal InRelease
The following signatures couldnā€™t be verified because the public key is not available: NO_PUBKEY 66EFE2D582CE5D8A
Reading package listsā€¦

W: GPG error: http://ppa.launchpad.net/jtaylor/keepass/ubuntu focal InRelease: The following signatures couldnā€™t be verified because the public key is not available: NO_PUBKEY 7858088158B80F90
E: The repository ā€˜http://ppa.launchpad.net/jtaylor/keepass/ubuntu focal InReleaseā€™ is not signed.
W: GPG error: http://ppa.launchpad.net/snappy-dev/image/ubuntu focal InRelease: The following signatures couldnā€™t be verified because the public key is not available: NO_PUBKEY F1831DDAFC42E99D
E: The repository ā€˜http://ppa.launchpad.net/snappy-dev/image/ubuntu focal InReleaseā€™ is not signed.
W: GPG error: http://ppa.launchpad.net/yktooo/ppa/ubuntu focal InRelease: The following signatures couldnā€™t be verified because the public key is not available: NO_PUBKEY 66EFE2D582CE5D8A
E: The repository ā€˜http://ppa.launchpad.net/yktooo/ppa/ubuntu focal InReleaseā€™ is not signed.

Could you please run ncp-report and share output via pastebin?
How did you install? (Link to procedure, docs or howto please?)
ppaā€™s ar not part of regular ncp Debian installation afaik.

Thank you, here is the report:

Sorry I cannot find the docs how I installed, this was 2-3 years ago, but I did it via apt. Does that help? It was working well until I moved to another city.

Sorry i do not use Ubuntu or PPA. But i think you must add the key.
If NextcloudPi has got a meachnism please do not test it:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys F1831DDAFC42E99D

I do not us Ubuntu or ppaā€™s either.
He must have added them manually

Yes, I added them manually. I am using Debian btw. Is the installation method import? As stated, it worked so far, just suddenly I have this problem.