Proxy YUM - No available modular metadata for modular package

Hi community,
I just set up a nexus 3.26.1-02 repo.
I want to use it as a proxy yum.
I have declared the centos 8 base, appstream, epel8 …
and if i try to install an httpd package I have the error No available modular metadata for modular package.
I no longer have any leads.
Here is the trace

yum install httpd -y -v
Plugins chargés : builddep, changelog, config-manager, copr, debug, debuginfo-install, download, generate_completion_cache, needs-restarting, playground, product-id, repoclosure, repodiff, repograph, repomanage, reposync, uploadprofile
YUM version: 4.2.17
cachedir: /var/cache/dnf
User-Agent: constructed: ‘libdnf (CentOS Linux 8; generic; Linux.x86_64)’
dépôt : téléchargement à distance en provenance de : vdm-centos8
VDM Centos 8 base 28 MB/s | 8.0 MB 00:00
vdm-centos8 : utilisation des métadonnées depuis le jeu. 26 nov. 2020 09:25:19 CET.
Dernière vérification de l’expiration des métadonnées effectuée il y a 0:00:01 le jeu. 26 nov. 2020 09:42:44 CET.
Aucun module par défaut n’a été trouvé
Completion plugin: Generating completion cache…
–> Début de la résolution des dépendances
—> Le paquet httpd.x86_64 2.4.37-21.module_el8.2.0+494+1df74eae sera installé
—> Le paquet httpd-filesystem.noarch 2.4.37-21.module_el8.2.0+494+1df74eae sera installé
—> Le paquet httpd-tools.x86_64 2.4.37-21.module_el8.2.0+494+1df74eae sera installé
—> Le paquet mod_http2.x86_64 1.11.3-3.module_el8.2.0+486+c01050f0.1 sera installé
—> Le paquet centos-logos-httpd.noarch 80.5-2.el8 sera installé
–> Résolution des dépendances terminée
Dépendances résolues.

Paquet Architecture Version Dépôt Taille

Installation:
httpd x86_64 2.4.37-21.module_el8.2.0+494+1df74eae vdm-centos8 1.7 M
Installation des dépendances:
centos-logos-httpd noarch 80.5-2.el8 vdm-centos8 24 k
httpd-filesystem noarch 2.4.37-21.module_el8.2.0+494+1df74eae vdm-centos8 36 k
httpd-tools x86_64 2.4.37-21.module_el8.2.0+494+1df74eae vdm-centos8 103 k
mod_http2 x86_64 1.11.3-3.module_el8.2.0+486+c01050f0.1 vdm-centos8 156 k

Résumé de la transaction

Installer 5 Paquets

Taille totale des téléchargements : 2.0 M
Taille des paquets installés : 5.5 M
Téléchargement des paquets :
(1/5): httpd-filesystem-2.4.37-21.module_el8.2.0+494+1df74eae.noarch.rpm 545 kB/s | 36 kB 00:00
(2/5): httpd-tools-2.4.37-21.module_el8.2.0+494+1df74eae.x86_64.rpm 1.0 MB/s | 103 kB 00:00
(3/5): mod_http2-1.11.3-3.module_el8.2.0+486+c01050f0.1.x86_64.rpm 3.4 MB/s | 156 kB 00:00
(4/5): httpd-2.4.37-21.module_el8.2.0+494+1df74eae.x86_64.rpm 14 MB/s | 1.7 MB 00:00
(5/5): centos-logos-httpd-80.5-2.el8.noarch.rpm 291 kB/s | 24 kB 00:00

Total 11 MB/s | 2.0 MB 00:00
Test de la transaction
No available modular metadata for modular package ‘httpd-2.4.37-21.module_el8.2.0+494+1df74eae.x86_64’, it cannot be installed on the system
No available modular metadata for modular package ‘httpd-filesystem-2.4.37-21.module_el8.2.0+494+1df74eae.noarch’, it cannot be installed on the system
No available modular metadata for modular package ‘httpd-tools-2.4.37-21.module_el8.2.0+494+1df74eae.x86_64’, it cannot be installed on the system
No available modular metadata for modular package ‘mod_http2-1.11.3-3.module_el8.2.0+486+c01050f0.1.x86_64’, it cannot be installed on the system
Les paquets téléchargés ont été mis en cache jusqu’à la prochaine transaction réussie.
Vous pouvez supprimer les paquets en cache en exécutant « yum clean packages ».
Erreur : No available modular metadata for modular package

no one has an idea ?
Please, it’s very important.

ok i found it
Is by what i used a group. My group contained a proxy yum of Base Centos 8 and Stream Centos 8. And the metadata file of the first one was overwritten by the second.
Was my config bad or is it impossible to use a group in this case?
Here are the urls of my 2 proxy
http://mirror.centos.org/centos/$version/AppStream/$arch/os
http://mirror.centos.org/centos/$version/os/$arch
and the configuration of my repo file :

[vdm-centos8]
name=VDM Centos 8 base
baseurl=http://<host>:8080/repository/group-centos8/
enabled=1
gpgcheck=1
repo_gpgcheck=0
priority=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial

As far as I know metadata shouldn’t be being overwritten.
I know we did make some fixes including in the upcoming 3.29 version.
My suggestion would be on release you upgrade to that and if still having issue file a ticket in our defect tracker (unless anyone else has advice): issues.sonatype.com.