When creating an extractor from the same source you have already set up, you decided to copy the password from a different configuration, which is already connecting to the data source. However in the first run you got this error:
Encryption error: Invalid cipher text for key <key_name>
The issue is that you copied the password from a different configuration. Keboola uses an encryption algorithm, that makes sure your passwords are not stored in plain text in the configuration (and hence unprotected). The encryption is project and component specific - this means that if you are using a Generic extractor in one project and you input a password and save the configuration, the resulting cipher text will be different than if you did exactly the same in a different project. So if you are copying a configuration and not using the Copy to new configuration option, always insert the actual password please and hit save.
For more information about how Keboola encrypts your passwords please refer to https://developers.keboola.com/overview/encryption/#ui-interaction.