The error message you provided indicates that there's a permission issue when trying to extract a file from the backup directory. Specifically, it's encountering a problem when trying to create a symlink.

Here are the steps you can take to resolve this issue:

1. Check User Permissions:

   • Make sure the user trying to extract the file (username in this case) has the necessary permissions to read from and write to the /home/username/backups/ directory.

2. Check File Ownership:

   • Ensure that the files inside the backup directory are owned by the same user (username) who is trying to extract them.

3. Check Permissions on Destination Directories:

   • Verify that the directories where the extraction is happening have the correct permissions. The user should have permission to write to those directories.

4. Check if SELinux or AppArmor is Enabled:

   • If you're using SELinux or AppArmor, they might be enforcing security policies that prevent certain operations. You may need to adjust the policies to allow the necessary actions.

5. Check for Existing Files or Symlinks:

   • Ensure that there are no existing files or symlinks in the destination directory that might conflict with the extraction process.

6. Try Using sudo:

   • If the extraction requires elevated privileges, try running the extraction command with sudo to ensure that it has the necessary permissions.

7. Check Filesystem Type:

   • If you're working with a non-standard filesystem, it's possible that there are specific permission or capability restrictions in place.

8. Temporary Directory:

   • Ensure that the temporary directory (/bin/tar) has the necessary permissions for creating symlinks.

9. Check if MySQL is Running:

   • Ensure that MySQL is running and that the /var/lib/mysql/mysql.sock file or symlink exists.

10. Check for File Locks:

• There might be file locks or other processes preventing the creation of the symlink. Check if any other processes are accessing or locking the files.

11. Disk Space:

• Ensure that there is enough disk space available on the filesystem where the extraction is happening.

12. Review the Extraction Command:

• Double-check the extraction command and parameters to make sure they're correct and not inadvertently causing issues.

After checking these points, try the extraction process again. If the issue persists, consider reviewing the specific permissions and settings on your system or consulting with a system administrator or support from your hosting provider for further assistance.