Digital signature not allowing me add another

Hi,

Hope you are doing well.

As shared above, the document has already been signed by someone else. Signing is the final process, once signed the document becomes restricted to make any further changes. 

So, when it was signed by someone else. Then you can't apply your signature on the same document. Unless its sent to you via Adobe Sign.

There is a process of getting one document signed by multiple people. For that you need to send the document to respective signers using Adobe Sign service with the signature fields assigned to each signer. 

https://helpx.adobe.com/sign/using/send-document-for-signature.html 

Hope this answers your question. 

Let us know if you are receiving the document through same method, but still can't sign it. 

Thanks,

Akanchha