Freeswitch v1.10, debian10.4 , build failed, any sugestion are welcome !

cat /usr/src/freeswitch-debs/log/builds-ok.txt

true

cat /usr/src/freeswitch-debs/log/buster-amd64.txt |more

Warning: apt-key output should not be parsed (stdout is not a terminal)

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## Creating base buster-amd64 image...

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Using custom sources /tmp/fs.gpg buster /tmp/fs.sources.list

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## Using apt sources file: /tmp/fs.sources.list

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I: Invoking pbuilder

I: forking: pbuilder create --keyring /tmp/fs.gpg --othermirror 'deb  https://mirrors.ustc.edu.cn/debian/ buster main|deb  https://mirrors.ustc.edu.cn/

debian-security buster/updates main|deb  https://mirrors.ustc.edu.cn/debian/ buster main|deb  http://files.freeswitch.org/repo/deb/debian-unstable/ buster

main' --buildplace /var/cache/pbuilder/base-buster-amd64.cow --mirror http://files.freeswitch.org/repo/deb/debian-unstable/ --architecture amd64 --distri

bution buster --no-targz --extrapackages cowdancer

W: /root/.pbuilderrc does not exist

I: Running in no-targz mode

I: Distribution is buster.

I: Current time: Sat Jul 11 11:28:28 CST 2020

I: pbuilder-time-stamp: 1594438108

I: Building the build environment

I: running debootstrap

/usr/sbin/debootstrap

I: Target architecture can be executed

I: Retrieving InRelease

I: Checking Release signature

E: Release signed by unknown key (key id D76EDC7725E010CF)

   The specified keyring /usr/share/keyrings/debian-archive-keyring.gpg may be incorrect or out of date.

   You can find the latest Debian release key at https://ftp-master.debian.org/keys.html

E: debootstrap failed

E: Tail of debootstrap.log:

amd64: ok

2020-07-11 11:28:30 URL:http://files.freeswitch.org/repo/deb/debian-unstable/dists/buster/InRelease [4589/4589] -> "/var/cache/pbuilder/base-buster-amd64.

cow/var/lib/apt/lists/partial/files.freeswitch.org_repo_deb_debian-unstable_dists_buster_InRelease" [1]

gpgv: Signature made Sat Jun 13 00:32:40 2020 CST

gpgv:                using DSA key 20B06EE621AB150D40F6079FD76EDC7725E010CF

gpgv: Can't check signature: No public key

E: End of debootstrap.log

W: Aborting with an error

E: pbuilder create failed

I: forking: rm -rf /var/cache/pbuilder/base-buster-amd64.cow

Using custom sources /tmp/fs.gpg buster /tmp/fs.sources.list

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