NavMesh Agent Stops on a platform lower than its destination

I am working on unity game and in my game i have multiple AI's with only 1 AI always following the player.
Following points describe my problem:

• There are 2 platforms Platform1 above Platform2, both having Navmesh baked on them, separately.
• When my player is on Platform1 the AI(navmesh agent) stops exactly below the player on Platform2(which is below Platform1). Whereas i want the AI to find a way (or an off mesh link) to go to the above platform .
• I coded and set the nearest off mesh point(Manual off mesh link) as the navmesh agent's destination, but then the AI character Stops on the off mesh point and does nothing(as it have stopped on an off mesh link, it should jump) .

I don't have any height mesh. Have not worked much with navmesh.
Any Help will be greatly appreciated.

 

having the same problem