My contacts birthdays 'calendar' does not show up in Nextcloud

Hi there!
I saw a post on which everyone agreed on the fact that the Contacts birthdays calendar is created/updated every time we edit or create a contact with a birthday date. But this is not the case for me.
After importing my contacts from a file, nothing happened. I created a new contact with a birthday date a couple of hours ago but there is still no contacts birthdays ‘calendar’, see below:

Please, can someone help me to troubleshoot this issue?
Many thanks!

From digging through Nextcloud posts (, it seems like this can only be done via console command.
Please create a gitlab-issue, so that this problem can be tracked by the devs.