Unable to activate Source theme

For some reason I’m unable to activate Source theme from the Design and Branding tab. Tried it several times, not working. Other theme is activating fine. I also tried it by downloading and activating, but doesn’t seem to work. Goes back to default theme.

Also for some reason it showing that there’s an update available, but when updating through ghost-cli, it doesn’t seem to find the update.

Node - 18.19.1
Ghost - 5.89.1
mysql - Server version: 8.0.39-0ubuntu0.24.04.1 (Ubuntu)
OS - Ubuntu 24.04 LTS

In the “/content/themes”, execute ls -l, what do you see for the “Source” theme

I’ve attached the screenshot below, now that you mention, it looks like the permissions are alright, with read and execute. Could it be another issue?

Apologies for late reply, the issue was source was by default activated and I didn’t understand that, after checking out the settings it seemed that it was activated! Thanks