# Previous Step

In order to get back to previous step, user need to call this method.

```swift
BiometridStandard.getInstance().previousStep(processId: processId, callback: self)
```

| Parameter                     | Description |
| ----------------------------- | ----------- |
| processId: **String**         | Process id  |
| callback: **ProcessCallback** | callback    |

## Implementation example

```swift
import UIKit
import BiometridStandardSDK

class ViewController: UIViewController, ProcessCallback {

    override func viewDidLoad() {
        super.viewDidLoad()
    }
    
    @IBAction func previousStepBtn(_ sender: Any) {
        BiometridStandard.getInstance().previousStep(processId: processId, callback: self)
    }
 
    func previousStepCallback(status: Bool, response: String?, error: Errors?) {
        print("status previous step", status)
        if error != nil {
            print(error?.rawValue)
            return
        }
        print("response previous step", response)
    }
}

```

## Callback params

| Parameter             | Description                   |
| --------------------- | ----------------------------- |
| status: **Bool**      | Method request status         |
| response: **String?** | All the response from the api |
| error: **Errors?**    | Errors associated enum        |
