New-ADUser: The object name has bad syntax - powershell

Question

I want to create a new AD user but it is showing error message like:
New-ADUser : The object name has bad syntax
At C:\Users\sa\Desktop\AD User Script.ps1:22 char:1
+ New-ADUser -Name "$displayName" -UserPrincipalName "($initials) ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : NotSpecified: (CN=fbfb regbgfn...IT,DC=,DC=it:String) [New-ADUser], ADException
+ FullyQualifiedErrorId : ActiveDirectoryServer:8335,Microsoft.ActiveDirectory.Management.Commands.NewADUser
$firstName = Read-Host "Indtast dit fornavn"
$middlename = Read-Host "Indtast dit mellemnavn (Hvis du ikke har et tryk Enter)"
$surname = Read-Host "Indtast dit efternavn"
$PlainPassword = "Admin100"
$SecurePassword = $PlainPassword | ConvertTo-SecureString -AsPlainText -Force
$group = Read-Host "Hvilken Gruppe? [1 - Help] [2 - Sof] [3 - In]"
$firstletter1 = $firstname.Substring(0, 1)
$secondletter = $firstname.Substring(0, 2)
$firstletter2 = $middlename.Substring(0, 1)
$firstletter3 = $surname.Substring(0, 1)
$displayName = "$firstName $middlename$surname"
if ($middlename -eq $Null) {
$initials = "$firstletter1$secondletter$firstletter3".ToLower()
Write-Host "$initials"
}
else {
$initials = "$firstletter1$firstletter2$firstletter3".ToLower()
Write-Host "$initials"
}
$Searcher = [ADSISearcher]"(sAMAccountName=$initials)"
$Results = $Searcher.FindOne()
If ($Results -eq $Null) {
If ($group -eq 1) {
New-ADUser -Name "$displayName" -UserPrincipalName "($initials)" -Path "OU=,OU=,OU-,OU=,DC=,DC=" -Enabled $true -AccountPassword $SecurePassword -ChangePasswordAtLogon $True -DisplayName "$initials" -GivenName "$firstname" -HomeDrive "P: \\fileshare\Privat\%$initials%" -Initials "$initials" -SamAccountName "$firstletter1" -Surname "$surname"
}

Answer 1

Can you check the UserPrincipalName and sAMAccountName formats. An example would be:
Name: John Smith
UPN: smithj#example.com
sAMAccountName : smithj
UPN Format
A UPN consists of a UPN prefix (the user account name) and a UPN suffix (a DNS domain name). The prefix is joined with the suffix using the "#" symbol. For example, "someone# example.com". A UPN must be unique among all security principal objects within a directory forest. This means the prefix of a UPN can be reused, just not with the same suffix.