You can change the general password expiration policies in the online GUI but for individual users and to check the state you need to use powershell.
- First make sure you have installed the required module for powershell.
 – Azure Active Directory Module for Windows Powershell.
 On Windows 10 you can open powershell with run as administrator and run the command:Install-Module -Name MSOnline
 Or you can download the installer from:
 http://connect.microsoft.com/site1164/Downloads /DownloadDetails.aspx?DownloadID=59185 /DownloadDetails.aspx?DownloadID=59185
 You need the AdministrationConfig-V1.1.166.0-GA.msi file.
 – For this to install you need to have the Microsoft Online services sign-in assistant > 7.
 If you don’t have it you can download it from:
 https://www.microsoft.com/en-us/download/details.aspx?id=41950
- Now that we have the necessary software we can connect, start powershell for windows azure ad and execute:
  
 Connect-MsolService
- Check if password expiration is set for any of the users:
 Get-MSOLUser | Select UserPrincipalName, PasswordNeverExpires
- Change password expiration for all users:
 Get-MSOLUser | Set-MsolUser -PasswordNeverExpires $true
 Get-MSOLUser | Set-MsolUser -PasswordNeverExpires $false
- Change password expiration for just one user:
 Set-MsolUser -UserPrincipalName u1@dm.tld -PasswordNeverExpires $true
 Set-MsolUser -UserPrincipalName u1@dm.tld -PasswordNeverExpires $false