Is that you are asking about editor users or the site visitor users?

I am asking about Commerce Manager (CM) editor user. My CMS admin user of member group webadmins and webeditors cannot access CM and I can only access with default username/password admin/store.

Hi Muller

I just created a user for commerce manager. You need to create a user in CMS that has administrator role. You can login with this user in commerce manager. I hope that helps.

Episerver Commerce has its own groups that you use to assign access rights for Commerce functions.

You must manually create the CommerceAdmins, CommerceSettingsAdmins and CatalogManagers groups before adding users to them. To do this, go to CMS > Admin > Access Rights > Administer Groups

Find more details here

Apparently I was replying to the wrong thread.

You should be mentioning if you are using ASP.NET Membership Provider or AspNetIdentity. 

You also mentioned We have a separate login for Commerce Manager (CM) user and CMS user. which is strange. Does that mean you use different membership providers for CMS and Commerce Manager