New Nextcloud 25 is added into my Debian 11 (Bullseye) repository, feel free to use (Latest builds https://apt.jurisic.org/ . Check how to add repository here).
If You're already using Nextcloud from Jurisic repository, upgrade process from 24 to 25 is very simple:
sudo apt update
sudo apt upgrade
sudo occ db:add-missing-indices
sudo occ db:convert-filecache-bigint
sudo occ app:update --all
