Error installing

Added nexus - http://localhost:8081/repository/nuget-group/ (Priority 0)
PS C:\Users\Shimul> choco install nexus
Chocolatey v2.2.2
Installing the following packages:
nexus
By installing, you accept licenses for the packages.
Invalid credentials specified.
Please provide credentials for: http://localhost:8081/repository/nuget-group/
User name: admin
Password: ************************
Unable to connect to source ‘http://localhost:8081/repository/nuget-group/’:
Failed to fetch results from V2 feed at ‘http://localhost:8081/repository/nuget-group/Packages()?$filter=(tolower(Id)%20eq%20’nexus’)%20and%20IsLatestVersion&semVerLevel=2.0.0’ with following message : Response status code does not indicate success: 502 (The group repository nuget-group contains a proxy with different nuget version).
nexus not installed. The package was not found with the source(s) listed.
Source(s): ‘http://localhost:8081/repository/nuget-group/
NOTE: When you specify explicit sources, it overrides default sources.
If the package version is a prerelease and you didn’t specify --pre,
the package may not be found.
Please see Chocolatey Software Docs | Troubleshooting for more
assistance.

Chocolatey installed 0/1 packages. 1 packages failed.
See the log for details (C:\ProgramData\chocolatey\logs\chocolatey.log).

Failures

  • nexus - nexus not installed. The package was not found with the source(s) listed.
    Source(s): ‘http://localhost:8081/repository/nuget-group/
    NOTE: When you specify explicit sources, it overrides default sources.
    If the package version is a prerelease and you didn’t specify --pre,
    the package may not be found.
    Please see Chocolatey Software Docs | Troubleshooting for more
    assistance.
    PS C:\Users\Shimul>
    Please help for some reason it is not finding my package inside of the group

There may be more than one problem, but notice this in the error message you posted:

The group repository nuget-group contains a proxy with different nuget version

You can’t mix v2 and v3 proxies in the same group, they speak different protocols. See the note at the top of the page, here:
https://help.sonatype.com/repomanager3/nexus-repository-administration/formats/nuget-repositories/grouping-nuget-repositories

Hello
I only included one software in this application, why is my package not being found

There is a problem with the configuration of your Nexus Repository instance. If you’re not the administrator, you will need to contact your administrator.

Hello,
I forgot to mention I am using chocolatey