Improve controllers performance

**Problem**
When working with handlers, the error messages could be more descriptive.

**Suggestion**
Improve error handling and add detailed error messages.

**Context**
This would help with debugging and maintenance.

No file or test is named. Start by locating the controllers and handlers responsible for the reported errors, then read their existing error paths and tests if present. Done means the relevant failures produce more descriptive messages and the affected checks pass.

Written by the indexing model from the issue text.