Add license purchased under personal plan to Admin Console

Hi we always only ever had one user tht has a license purchased under a personal plan (account set up using work email).  We now have a second user so am now using the admin console.  The new users license was purchased and assigned from the admin console.  How can i pull in the other license?  I added that user, using the same email address but it doesn't show the license assigned to him (it does show if he signs into his personal account).