Yum group checksum issues

Hi all

I currently have Sonatype Nexus Repository Manager OSS 3.23.0-03 installed, and it is performing well overall. I do however have a problem. I have added all the relevant CentOS8 upstream repos as proxy repos in Nexus, and if I create individual repo files on my client machine under /etc/yum.repos.d/ then everything works as expected. But, if I group all these proxied repositories under one umbrella (group) repository called my-yum for instance, I cannot update my system. I get a

error: Downloading successful, but checksum doesn’t match. Calculated: 4796f61d927925e0faa77e5cd3f67ccf3ff62bc7870b87a5bf3baccfddeafb5d(sha256) Expected: b7e8eed732a1e168f70cd0e66479656cbf114b9e032219aed23078deaba14293(sha256) (http://nexus.mydomain.com:8081/repository/my-yum/repodata/comps.xml.gz)

This happens if I add just a single proxied repo to my “group” as well.
Any idea what I might be doing wrong? Or how I can fix this?

The idea I have is to create a single group repo which will in the end contain all the versions of applications we want to deploy, but we furnish our servers with a single repo file. Does this make sense?

This is just one of the upstream (proxied) repos in my-yum.
Example proxy repo config:

Remote Storage:


Example repo file config on client:

name=My CentOS8 YUM Nexus Repository

Thank in advance for anyone willing to help!