feat(ins): add more troubleshooting

Author: bene2k1

compute/instances/troubleshooting/fix-common-issues.mdx

@@ -108,9 +108,33 @@ This page list the most common issues you may encounter with your Scaleway Insta
    - Restart your Instance to re-upload the list of allowed SSH keys.
 
 ### Additional resources
-- [Scaleway Docs: How to generate an SSH key pair](/identity-and-access-management/organizations-and-projects/how-to/create-ssh-key/)
+- [Scaleway Documentation: How to generate an SSH key pair](/identity-and-access-management/organizations-and-projects/how-to/create-ssh-key/)
 - [OpenSSH Documentation](https://www.openssh.com/manual.html)
 
+## 5. How Can I recover access to my Instance?
+
+### Symptoms
+- You are unable to connect to your Instance via SSH.
+- Your SSH key is missing, or you cannot locate the corresponding private key.
+
+### Possible causes
+-  The private SSH key associated with the Instance was lost or deleted.
+-  The Instance’s SSH configuration or authorized keys file was altered, removing your access.
+
+### Troubleshooting tips
+
+- Check for another SSH key:
+   - Verify if another SSH key pair is associated with your [Scaleway account](https://console.scaleway.com/project/ssh-keys).
+   - Login using the alternative SSH key
+
+- Use the Scaleway console to add a new SSH key
+   - Upload another SSH key in the [SSH key section](https://console.scaleway.com/project/ssh-keys) of your Instance's Scaleway project.
+   - Reboot the Instance from the console to re-upload the new key to the Instance.
+
+### Additional resources
+- [Scaleway Documentation: How to generate an SSH key pair](/identity-and-access-management/organizations-and-projects/how-to/create-ssh-key/)
+- [Scaleway Documenation: How to power off your Instance](/compute/instances/how-to/power-off-instance/)
+
 ## My Instance is locked
 
 ### Symptoms