unable to reject spend authorized supplier request

Summary:

On the spend authorized approval flow, assignee is able to perform reject but the reject action is not being performed

Content (please ensure you mask any confidential information):

Hello experts,

We have a process that prospective suppliers are being promoted to spend authorized and during this process the approver might reject the request.

I've set the BPM to allow rejection and to force to enter comments

Also added option to get message when the task is complete to the creator (as there is no option to reject status)

but still the process is not getting reject and it is still on the pending approval