Hi,
Thank you for reaching out here in the DocuSign Community.
The following article explains common reasons for not being able to adopt a new signature while signing:
Why can't I change my signature?
https://support.docusign.com/s/document-item?bundleId=yca1573855023892&topicId=tpz1620246007465.html&_LANG=enus
I would highly recommend you to get in touch with DocuSign Support for assistance clearing this recipient data from our system so they can adopt a new signature. They can also try to create a free account.
Keep in mind that if further assistance is required, you can always submit a support case to have one of our experts assist you by clicking the link below:
https://support.docusign.com/en/contactSupport
If you are not able to open the case on this page, you should scroll down to 'More Support Options' and select "I can't reset my password or don't have an account." you will have the option to fill out a form or calling Support.
Best regards,
Franklin H. | DocuSign Community Moderator