Mailbox cannot be created as DL exist with same display name

[AC]

Hello Team, Have anyone experienced this , there is a Distribution List that exist with a certain name and mailbox with same name cannot be created. Im sure we can create a mailbox and DL with the same display name. Please help 

[#2]

The issue is not with the Display Name, but with alias/name values, so make sure you use something unique for those. PowerShell is the usual workaround, as it allows you to directly specify values for those, whereas the UI inherits them.

[#3]

Thank you Vasil