In the old version of App Store Connect, you could view historical rejection information. However, the revised version of 'App Store Connect' will only display the entrance to the Solution Center after being rejected, and then the entrance will disappear after being reviewed.
However, if you know the link to the solution, you can access the Solution Center by modifying your Apple ID (Apple Store Connect describes it as: an ID automatically generated for your app.)
https://appstoreconnect.apple.com/apps/
Your Apple ID/appstore/platform/ios/resolutioncenter?m=Your Apple ID