CentOS 9 Stream - errors doing yum update

I'm coming in from using Ubuntu.

Just installed CentOS on my DEV server and right away having issues just doing an update or installing new packages.

Here is the error:

sudo yum update

Last metadata expiration check: 0:41:22 ago on Tue 15 Feb 2022 10:38:21 AM.
Error:

 Problem 1: problem with installed package libidn2-2.3.0-7.el9.x86_64
  - cannot install the best update candidate for package libidn2-2.3.0-7.el9.x86_64
  - nothing provides libunistring.so.0()(64bit) needed by libidn2-2.3.2-1.el7.x86_64

 Problem 2: cannot install the best update candidate for package python3-tracer-0.7.5-4.el9.noarch
  - problem with installed package python3-tracer-0.7.5-4.el9.noarch
  - package python3-tracer-0.7.5-4.el9.noarch requires tracer-common = 0.7.5-4.el9, but none of the providers can be installed
  - cannot install the best update candidate for package tracer-common-0.7.5-4.el9.noarch
  - cannot install both tracer-common-0.7.8-1.el7.noarch and tracer-common-0.7.5-4.el9.noarch

Here are the enabled repos:

yum repolist enabled
repo id       repo name
appstream     CentOS Stream 9 - AppStream
baseos        CentOS Stream 9 - BaseOS
epel          Extra Packages for Enterprise Linux 7 - x86_64
extras-common CentOS Stream 9 - Extras packages
remi-safe     Safe Remi's RPM repository for Enterprise Linux 7 - x86_6

I have tried to:

sudo yum update --best --allowerasing

But its still complaining:

Problem 1: problem with installed package libidn2-2.3.0-7.el9.x86_64
  - cannot install the best update candidate for package libidn2-2.3.0-7.el9.x86_64
  - nothing provides libunistring.so.0()(64bit) needed by libidn2-2.3.2-1.el7.x86_64
 Problem 2: cannot install the best update candidate for package python3-tracer-0.7.5-4.el9.noarch
  - problem with installed package python3-tracer-0.7.5-4.el9.noarch
  - package python3-tracer-0.7.5-4.el9.noarch requires tracer-common = 0.7.5-4.el9, but none of the providers can be installed
  - cannot install the best update candidate for package tracer-common-0.7.5-4.el9.noarch
  - cannot install both tracer-common-0.7.8-1.el7.noarch and tracer-common-0.7.5-4.el9.noarch
(try to add '--skip-broken' to skip uninstallable packages)

Any ideas how to fix this?

UPDATE:

Tried

yum clean all
yum check
yum check-update
yum update

yum update --nobest

Same result:

Last metadata expiration check: 0:49:35 ago on Tue 15 Feb 2022 11:30:57 AM.
Dependencies resolved.

 Problem 1: cannot install the best update candidate for package libidn2-2.3.0-7.el9.x86_64
  - nothing provides libunistring.so.0()(64bit) needed by libidn2-2.3.2-1.el7.x86_64
 Problem 2: package python3-tracer-0.7.5-4.el9.noarch requires tracer-common = 0.7.5-4.el9, but none of the providers can be installed
  - cannot install both tracer-common-0.7.8-1.el7.noarch and tracer-common-0.7.5-4.el9.noarch
  - cannot install the best update candidate for package tracer-common-0.7.5-4.el9.noarch
  - cannot install the best update candidate for package python3-tracer-0.7.5-4.el9.noarch
==================================================================================================================================================
 Package                                Architecture                    Version                               Repository                     Size
==================================================================================================================================================
Skipping packages with conflicts:
(add '--best --allowerasing' to command line to force their upgrade):
 tracer-common                          noarch                          0.7.8-1.el7                           epel                           31 k
Skipping packages with broken dependencies:
 libidn2                                x86_64                          2.3.2-1.el7                           epel                          148 k

Try:

yum clean all
yum check
yum check-update
yum update

If there is still a problem, try:

yum update --nobest

Figured it out, I copy pasted and added epel from CentOS 7 so it was conflicting with existing one on the CentOS 9.

Used this to remove the older repo:

sudo yum remove epel-release-latest-7.noarch.rpm

FYI: there is apparently epel-next:

https://www.linuxcapable.com/how-to-install-enable-epel-epel-next-repository-on-centos-9-stream/

UPDATE:

As others mentioned there is an updated official guide to repos on CentOS9: https://docs.fedoraproject.org/en-US/epel/#_centos_stream_9