Landscape Issue

Ok so I have 4 raw files and I import them in and add them to a master level through world composition . and Here is what happens

They are lined up perfectly in the levels map, I need them to be seamed together yet they are not. I dont know how to convert the raw files to tiled landscape heightmaps or I would do it that way. This is a big land and an expensive one so I have to have a fix for this but I can not figure it out at all I tried it in 4.7.6 and 4./8 preview build. also when i smooth or scupt the land it pops the seams up

can I please get some help for this

Can I please get some help from Epic on this

What tool are you using to make these heightmaps? You need some overlap between the heightmaps, if you use World Machine there is an option for this when you output the tiled heightmaps, otherwise you’ll get seams like this.

Why use .raw file try using .png image format .I myself use it for creating terrain .I have not yet faced such problem.