This is happening for me but only with the water plugin. Totally messing up the terrain.
UE 5.0.3
Windows 10
Even with any of the default levels, with no changes by myself. E.g. load up the Open World, place a lake (water plugin). Save and close UE5. Load it up again, and BOOM, a super high tower of terrain with a lake at the top.
Maybe its cause you are on first layer, you should do on an other, then comes the βmiracleβ, tested on m1 ue5.1 is working, but the shaders arent ready yet, so do not change engine version on this cause.