my unity5.5 not find the NevmeshAgent???

i have problem in unity that is when i wrute the code of NevMeshAgent unity not found the intellisense of NevMeshAgent please somebody help me and favor me as much as possible.

yes this script giving the errors @itsharshdeep

Hi @Ranaiffi :

Sorry for late. Now I just Installed Unity 5.5.0 and try to reproduce the issue.
Now I came to know that We need to add the following line to access the navmesh scripts:

using UnityEngine.AI;

Please add this to resolve the error. Do let us know if still there is any error
Thanks