Adding Initials / Date of Sign

Hello!
I'm trying to add extra fields to a transaction through the REST API but I can't get the extra fields to show up.
So far I managed to add a free text field at the time of signing, but I can't get it to show the initials of the signer or the date of signing.

The payload I used is the following:

{"roles":[{"id":"emailexamplecom","index":0,"signers":[{"email":"[email protected]","firstName":"example","lastName":"example","company":"company"}]}],"documents":[{"name":"doc.pdf","approvals":[{"role":"emailexamplecom","fields":[{"page":0,"top":20,"subtype":"FULLNAME","height":60,"left":41,"width":200,"type":"SIGNATURE"},{"page":0,"top":17,"subtype":"TEXTFIELD","height":60,"left":286,"width":200,"type":"INPUT","extract":true},{"page":0,"top":16,"subtype":"INITIALS","height":60,"left":506,"width":200,"type":"SIGNATURE","extract":true},{"page":0,"top":75,"subtype":"DATE","height":60,"left":291,"width":200,"type":"SIGNATURE","extract":true}]}]}],"name":"test","type":"PACKAGE","language":"es","emailMessage":"e","description":"test","autocomplete":true,"status":"SENT"}

When creating the transaction, the API returns its id, indicating that it was created correctly.
However, when the recipient adds the document to sign, only the signature (with the fullname) and the text field appear. The initials and the date do not appear.

 Thank you very much!