Stuck on 14 and security August 2024

Just had to use Samsung care to replace my S24 ultra that was having issues. They sent me a replacement and I got everything setup and running. However I can't seem to get android 14 to update to 15 and I'm also stuck on security from August 2024 on my new replacement phone. My old phone I am sending back was on 15 and the most recent security update.

Being search online everywhere to fix this. I'm in the US and on xfinity for my carrier. Anyway to push the 15 update and security patches through? Or does it take time for the system to see I have a new phone?