Problem with a water

this is my first map creation
Here is my problem, as I make a map and check it puts me the following message: BP_IslandWaterPlane_6 more overriden materials (2) is static mesh component than are referenced (1) in mesh source "SM_OceanPlane_Newisland.

Someone could help me because I do not understand what’s wrong
Thank you, I really need help, I made the map, it starts to be textured, I have the ocean, but I can not test the map, nor upload to steam to test it

non personne pour un coup de mains ?