Herzum Approval - strange text in emails

[IT Accounts]

Снимок.JPG
This is a creenshot of letter's title in list of emails in Outlook. "Issueapprovalid=387" - this text only in this title, there is no such text in letter's body. What is that and how we can erase it from letters? 

Thank you! 

Снимок.JPG ‏11 KB

[Antonella Capalbo]

The displayed number (e.g. 387) is the unique Approval identifier.
It is needed in order to evaluate which Approval must change its status when the approver replies to an Approval Request via e-mail.

Some email clients doesn't render the text, Outlook renders it.

It is not possible to erase it from letters.

Regards,
Antonella