Warning .env file not found! indicates that user's .env file is not reahable from OpenPanel UI container.

OpenPanel UI docker cntianer mounts /home/:/home/
and if the inode number changes for the home directory, then /home
in docker no longer reflects the files on /home on the host OS.
if they show different data, then this issue affects your user!
Solution is to simply stop and restart openpanel ui:
cd /root && docker compose down openpanel && docker compose up -d openpanel