Many users have complained about this issue, which likely affects all #Windows11 users who upgrade to the 24H2 version. Running 'SFC Scannow' made no difference to the cache. Irrespective of users, the #DiskCleanup shows the file size as 8.63GB.

Undeletable 8.63GB cache emerges in latest Windows 11 #24H2Update — checkpoint updates were the culprit, and #Microsoft is working on a fix
https://www.msn.com/en-us/news/technology/undeletable-8-63gb-cache-emerges-in-latest-windows-11-24h2-update-checkpoint-updates-were-the-culprit-and-microsoft-is-working-on-a-fix/ar-AA1s2ZOL?ocid=emmx-mmx-feeds&cvid=a98318cddfaa4b9d97604de2695a3646&ei=15&PC=EMMX01