Roundcube login impossible

My YunoHost server

Hardware: VPS bought online
YunoHost version: 11.2.10.3
I have access to my server : Through SSH | through the webadmin
Are you in a special context or did you perform some particular tweaking on your YunoHost instance ? : no

If your request is related to an app, specify its name and version: roundcube 1.6.6~ynh2

Description of my issue

When trying to connect to Roundcube either through the portal or directly via the app URL, I get a connexion failed message. I’ve double checked the id and password… haven’t done any tweaking of the app config files.
I saw an unanswered message dealing with the same issue in the french forum.
Anyone got a clue as to why this is happening?
Thx for any help you can provide me with :slight_smile: