`set_hl` not applies color (set highlight problem)

[RAprogramm]

    let header_highlight = nvim_oxi::api::opts::SetHighlightOpts::builder()
        .foreground("#FF0000")
        .strikethrough(true)
        .bold(true)
        .build();

    handle_error(
        nvim_oxi::api::set_hl(0, "Header", &header_highlight),
        "Failed to set highlight for Header",
    )?;

in neovim's cmd line:

:hi Header                                                                                                                                                                                                
Header xxx cterm=bold,strikethrough gui=bold,strikethrough   

when i try to set highlights colors not apply.

like that in the Cargo.toml:

...
[dependencies]
nvim-oxi = { version = "0.5.1", features = ["neovim-0-10", "test", "neovim-nightly"] }
...

[RAprogramm]

Thank you!