Usage of Redirect URI always results in error: Error: Class "League\Uri\UriString" not found

Recently hit this issue.

The cause in my case was the second level dependency league/uri-interfaces which was being installed at version 7.0.0-beta.2.
uri-interfaces should contain the UriString class but in the beta.2 version it does not.

We would like to use league/uri-interfaces:7.0.0 but this requires psr/http-message ^1.1 || ^2.0 which is incompatible with drupal/core-recommended:9.5.8.

```
drupal/core-recommended 9.5.8 requires psr/http-message (~1.0.1)
```

For now I'm solving the problem by explicitly locking league/uri to 6.7.0 in my composer.json

```
composer require league/uri:6.7.0
```

@genebobmiller - thanks that helped - downgrading to 6.7.0

I have downgraded to 6.7.0 but now it is showing this error:

League\OAuth2\Server\Exception\OAuthServerException: The resource owner or authorization server denied the request. in League\OAuth2\Server\Exception\OAuthServerException::accessDenied() (line 243 of /my.website.com/public_html/app/vendor/league/oauth2-server/src/Exception/OAuthServerException.php).

Any idea how to resolve this issue? This all started when I upgraded Drupal core from 9.5.10 to 9.5.11.

Hi

In my case i did as @genebobmiller said (to downgrade and lock on 6.7.0) but alsi I locked league/uri-interfaces to 2.3.0
Now it works for me

Thnks

You'll face this problem if you've run `composer update`. Revert to the `composer.lock` before update command and you shall be good.