365 Apps Admin Center - certain devices not showing "last user" data.

Good afternoon Everyone. 

During some routine checks, we found that machines onboarded since jjjjj have blank data for "Last Contact". "Last User" and "Last Email" in the 365 Apps Admin Center Inventory. 

ENTRA and INTUNE have Colleagues correctly assigned but blank in 365 AAC. 

Has anyone seen or hopefully rectified this previously?

Thanks in advance.