Your workspace is active on the Hobby plan with no restrictions, and your "App" service's latest deployment is in a successful state, so there is nothing on the platform side preventing you from editing variables or redeploying. To deploy from a different branch, you can change the configured branch in your service's Settings tab under the Source section, and to edit variables, navigate to the Variables tab of the service - could you share a screenshot of what you're seeing when you attempt these actions?

Ditto!

We still need a screenshot or description of the specific error you're seeing when trying to edit variables or redeploy from a new branch. Your workspace and service appear active with no platform-side restrictions, so we need to see what's happening on your end to investigate further.