First up , is this question really about Maestro API? that’s where you posted it, so I think it’s not related to Maestro, right?
Also, not sure what you mean by blurry, can you share a screenshot by any chance? What API call did you make? 

Hola

Api productiva para mandar a crear un sobre

{{docusign}}accounts/{{api_account_id_docusign}}/envelopes

Mando un html que contiene toda la informaicón de un contrato a firmar en base64

{

"emailSubject": "GPO-DIR-US--9272716-202210",

"documents": "

{

"documentId": "1",

"name": “contracto",

"fileExtension": "html",

"documentBase64": "JzxodG1sPjxib2R5PjxoMT5HcnVwbyBKdW1leDwvaDE+PGgxPmJyaWRlPC9oMT48aDE+U0lHTkFUVVJFX1JFUFJFU0VOVEFUSVZFPC9oMT48L2JvZHk+PC9odG1sPic="

}

],

"recipients": {

"signers": r

{

"email": "joancarlosponce@gmail.com",

"name": "joan carlos ponce",

"recipientId": "1",

"routingOrder": "1",

"roleName": "Signer",

"emailNotification" : null,

"tabs": {

"signHereTabs": b

{

"anchorString": "BRIDE",

"anchorXOffset": 0,

"anchorYOffset": 0,

"anchorUnits": 0,

"anchorIgnoreIfNotPresent": "false",

"anchorCaseSensitive": "false"

}

]

}

},

{

"email": "joancarlosponce@gmail.com",

"name": "rosario",

"recipientId": "2",

"routingOrder": "2",

"roleName": "Signer",

"emailNotification" : null,

"tabs": {

"signHereTabs": b

{

"anchorString": "SIGNATURE_REPRESENTATIVE",

"anchorXOffset": 0,

"anchorYOffset": 0,

"anchorUnits": 0,

"anchorIgnoreIfNotPresent": "false",

"anchorCaseSensitive": "false"

}

]

}

}

],

"carbonCopies": e

]

},

"status": "sent",

"envelopeExpiration": {

Ejemplos asi se muestra cuando reviso directo en mi 

https://apps.docusign.com/send/documents/details/e8adc

Y asi cuando les llega el correo a mis firmantes