That sounds like the AOR. Does it have your application number? If so, try linking the application to GCKey.
Eh I seconded what alex00 said. That sounded like AOR - Does it look something like this? if yes, then it is AOR (ahh not sure if I could attach an image so I copied and pasted)
Immigration, Refugees and Citizenship Canada: Information about Application No. XXXXX
Correspondence Id: 2-88530600605
2 messages
Do Not Reply - Ne Pas Repondre <
Client-update-mise-a-jour@cic.gc.ca> Tue, Dec 12, 2023 at 9:15 AM
Reply-To:
donotreply@cic.gc.ca
To: sponsor's email
UCI: XXXX
Application No.: FXXXXXXXXX
Quote these numbers when corresponding with our office.
This is an automated message. Please DO NOT RESPOND to this message.
Dear Sponsor's name
This confirms that your application to Sponsor a Member of the Family Class has been received by Citizenship and Immigration
Canada (CIC) on 2023/11/20 on behalf of the following member(s):
PA's name
blah blah