Landscape rendered like mosaic on android

Hello, I am trying to use landscape for an android game. The landscape looks fine in editor (with or without android vulkan preview); but on my cellphone, the landscape looks like mosaic (having obvious rectangles).
Other items (staticmesh, pawn, and so on) look fine, it is only the landscapes. This should not be a problem of a special landscape, as I tested several maps from the marketplace and all I have tested show this phenomenon.

I am using UE5.3.2, the project is created for moblie, scalable. My cellphone is snapdragon 8gen1.

How should I fix this? Anyone has any ideas? Thanks in advance.

I have figured out what the problem is. In case someone facing the same issue, I post what I have found here.

I was inspired by this thread (Android Landscape texture). On android, multi-layer landscape material is not supported (so landscape painting is impossible). It is neccessary to write everything into a single layer of material.

The picture below is UE’s vehicle template with a singlelayer material from Epic’s “Soul City”. It looks pretty good on my cellphone.

You can rewrite your painting logic into your landscape material (instead of painting it manually); or (if it is impossible) use a staticmesh as replacement.