To sign with double authentication from the mail you must follow the following instructions:
Enter the email that you received from the platform and click Sign Document.
Check the document to sign.
If you have any comments, click Reject and enter the reasons for rejection.
If you agree, click on Sign, a window will open where you must enter your RUT, document number and select Next Step.
You will receive a text message to your cell phone with six digits, which you must enter to activate the multiple authentication factor. Once entered, click Next Step.
You will have to download the authenticator app:
Go to your phone's app store
Search for 'Google Authenticator' or 'Authy'.
Download the application.
Scan the QR code below on the APP.
Enter the code generated by the authenticator app and click Next Step.
Confirm your name and click Sign Document.
Once all the signers of the ceremony complete the electronic signature, a copy of the signed document will arrive by email.