Container Station/Docker Error : Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

Hi.

Got a Qnap NAS TS-230 with two disks (no RAID, only network access disks). Version of QTS is 5.2.3.3006. Container station is installed and works fine.
Installed Watchtower (that worked some time ago) and Portainer from Docker Hub to maintain my apps in docker.
Both got the same error : “Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?”
I connected my NAS with SSH and explored the files. It seems that there is no docker.sock in /var/run directory but docker.sock= (yes, with a “=”, maybe for security reasons).
Is that normal ?
Cannot copy or do anything to the file.

How could I get these apps working ?

If there is no solution, how to update an app (Jellyfin) in Qnap Container Station (all the tutos I found have access to a console which is not the case in Container Station).

Thanks for help.