Unable to create record from CRM to AX through plugin

Hi Experts,

When ever a contact is created in CRM the same has to be integrated to Dynamics AX. Where Ax has given a service to consume it. If i run through console application it works fine and  the record is getting created in AX but the same i tried through plugin it is giving the below error.

System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.IdentityModel.Clients.ActiveDirectory, Version=2.22.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified 

 But i have added the reference Microsoft.IdentityModel.Clients.ActiveDirectory .

We are using D365 (V9) online .

Please suggest.