# invalid_block

> This block cannot be saved to the library.

**Block cannot be saved** · HTTP 422

## What it means

This block cannot be saved to the library.

## What to do

Save a block of a type the library accepts.

## Example

```json
{
  "type": "https://api.bymundi.com/problems/invalid_block",
  "title": "Block cannot be saved",
  "status": 422,
  "detail": "This block cannot be saved to the library.",
  "code": "invalid_block",
  "requestId": "req_…"
}
```

How to read any error: [Errors guide](https://api.bymundi.com/docs/guides/errors.md).