Assign licenses to groups

[ArneDD]

Oftentimes it's much more conveniert to assign licenses via groups and not to the individual users.
However in the Azure portal for some of my groups, there is no licenses tab and also, when I choose the way way round and click on the general licenses button and try to assign a license to a group, the same groups don't show up in the list.
I was not able to find out why I can assign licenses to some groups but not to others.
Take for example these two Groups. I can't find a difference, but one can be assigned licenses to but not to the other:

What might be the reason?

[#2]

I noticed when I create the Microsoft 365 group in the Microsoft 365 Admin Center, the Licenses option (in Azure AD) is not available. If I create the Microsoft 365 group in Azure Active Directory, the Licenses option is available.

[#3]

Thanks @TomWechsler, that helped me to find the reason.
It's not really the group type that matters, but a property called: "securityEnabled". This is always "true" for security groups but for Microsoft365 it can be "true or false".
If this is set to "false" you cannot assign licenses to the group.
If you create a new group via Teams or admin.teams.microsoft.com, then it is a Microsoft365 group and the property "securityEnabled" is automatically set to "false".
The same thing happens when you create a Microsoft365 group through https://portal.office.com/.
However, if you create a Microsoft365 group via portal.azure.com, then "securityEnabled" is automatically set to "true".
Just one of the daily riddles that Microsoft presents to its users.