I have a scenario which I cant get my head around...

I have an organization with  several licenses for CRM, 45 for Microsoft Dynamics CRM Online Professional and 4 for Microsoft Dynamics Marketing Online Enterprise. 

My understanding at present is that the Enterprise license contains all the functionality of the Professional license plus Microsoft Dynamics Marketing Enterprise so do not need a professional license to access the CRM module


The organisation uses active directory synced to O365. 


The situation I have is that when I assign a user an enterprise license they are then unable to access CRM as they are advised they do not have a license but they can log in to the Https://xxx.marketing.dynamics.com


However when I assign them a professional license only they can access both urls.Https://xxx.crm.dynamics.com    and Https://xxx.marketing.dynamics.com  


Which I believe should not be the situation as I would expect that only users with an enterprise licence should have access to the Marketing url?


Are there any changed which need to be made in AD?