Error within a pipeline - docusign

I am having an error within a pipeline, I think that is the email of the recipent.

the error message is this: 

"Remote service reported an error: The email address for the recipient is invalid. The recipient Id follows. Recipient Id: 1"

I am populating the client email (recipient) with quickbase information.

Please if somebody could solve something like this, I need your help.

Thanks!

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Francisco Ojeda
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