Is it available if you go to Personalizations for the page? maybe it just needs to be set to Rendered - True.
I would start an SR. I found this note, but I was able to reproduce it in my system also and we do NOT use AME...
AME: PO_AME_APPROVAL Notification Does Not Display Amount Agreed in CPA/BPA (Doc ID 1637368.1)
This Note already read, but this is not the problem.
thanks and regards,