Service Desk e-mail notification for approval, button does not work

[Serge Masson]

Hello,

We created our first JIRA ServiceDesk workflow, for Service Request with approvals.

When we reach a status with approval, there is an e-mail notification. In this e-mail, there is two button : "Approve", "Decline"

Both button links to an error page : "Cannot find issue".
The link adress of the button : https://host.domain.com/servicedesk/customer/user/approval-action/PM-15/6/approve?sda_source=notification-email

But the issue is visible in the "Approvals" part of customer portal. And I can approve it from the button in the portal

JSD Version 3.12.2

Does anybody have a suggestion to help me ? 

Thanks in advance
Best regards