We can add multiple signers to a Docusign. As long as 2 people are signing we can mark the document as done/complete.
Currently I am not able to find an API function to mark it as done/complete.
I tried to delete the other signers but I just get back "The recipient could not be deleted. Recipient not in state that allows correction."
I also found this SO answer but the link in the answer is broken: https://www.docusign.com/support/classic/documentation/cdse-user-guide/advanced-sending/using-any-signer-option
I assume the feature used to be there, and Docusign removed it.
I don't understand your question. By design, it is not possible to programmatically mark an envelope or signing recipient as complete (signed).
An envelope becomes complete after all of the recipients are complete. And a signing recipient only becomes complete after they have signed the envelope.
I'm not sure that you can delete all of the signers if there are no other recipients (since an envelope needs at least one recipient).
The usual reason for not being able to delete a recipient is that the envelope is currently assigned to that recipient. (You need to delete the recipient before they are the current recipient.)
You may want to ask a new question where you describe: