Recipients not able to Review and Sign a document, only have Delegate available

We are having an issue with some clients that haven't been able to open a document to sign as the 'Review and Sign' button is not in the email.

Other clients have not had this problem.

Tried to do a Support Chat without any luck.  Also tried to ring a support line which was given by the chat person only to get a messsage saying the number is not connected.

This also seems to have happened since the recent update. 

We have just noticed the 2 recipients with this problem have 'westnet' email addresses.  Could this have something to do with the problem?

From other posts I can see that by sending a Reminder for the document works but this does not solve the problem.
Thank you.