How does one bulk import contacts into exchange; some with duplicate proxy addresses?

We are trying to bulk import contacts with CSV as follows: Import-Csv .\ExternalContacts.csv|%{New-MailContact -Name $_.Name -DisplayName $_.Name -ExternalEmailAddress $_.ExternalEmailAddress -FirstName $_.FirstName -LastName $_.LastName} We get an error because some contacts have the same proxy addresses attribute. There are multiple doctors with the same address (ie: [email protected]). How would one fix this or work around it?

Get information about MAC address

My router (FritzBox 7330) shows tons of errors about a device that continuously try to connect to my network: 23.12.19 10:17:07 Registrazione del dispositivo wireless fallita: chiave wireless non valida. Indirizzo MAC: xx:xx:xx:xx:xx:xx. 23.12.19 10:16:55 Registrazione del dispositivo wireless fallita: chiave wireless non valida. Indirizzo MAC: xx:xx:xx:xx:xx:xx. 23.12.19 10:16:43 Registrazione del dispositivo wireless fallita: chiave…