FFmpeg avutil.lib unresolved external symbol

Question

i'm trying to use FFmpeg with visual sudio 2022 .NET 6 through an MSVC project. I followed this tutorial: https://www.youtube.com/watch?v=qMNr1Su-nR8&ab_channel=HakanSoyalp. I mean I have configureg Include (.h) file, library (.lib) files and dynamic (.dll) file copied into bin folder. If I call for example the avformat_alloc_context() method inside the avformat.lib all work rightly, if I call for example av_file_map(...) inside the avutil.lib the compiler give me an error: LNK2019 unresolved external symbol "int __cdecl av_file_map ... But the avutil.lib is linked!!! The same happen if I call other methods inside avutil.lib module.

Thanks for help...

Code:

extern "C"
{
    #include <libavformat/avformat.h>
    #include <libavutil/file.h> // av_file_map
}

int ConvertJPEGtoNALs(int argc, char* argv[])
{
    AVFormatContext* fmt_ctx = NULL;
    AVIOContext* avio_ctx = NULL;
    uint8_t* buffer = NULL, * avio_ctx_buffer = NULL;
    size_t buffer_size, avio_ctx_buffer_size = 4096;
    char* input_filename = NULL;
    int ret = 0;
    struct buffer_data bd = { 0 };
    if (argc != 2) {
        fprintf(stderr, "usage: %s input_file\n"
            "API example program to show how to read from a custom buffer "
            "accessed through AVIOContext.\n", argv[0]);
        return 1;
    }
    input_filename = argv[1];
    /* register codecs and formats and other lavf/lavc components*/
    //av_register_all();    //!deprecated
    /* slurp file content into buffer */
    ret = av_file_map(input_filename, &buffer, &buffer_size, 0, NULL);
    /* fill opaque structure used by the AVIOContext read callback */
    bd.ptr = buffer;
    bd.size = buffer_size; ???
    if (!(fmt_ctx = avformat_alloc_context())) {
        ret = AVERROR(ENOMEM);
        goto end;
    }
    //... to be continue ...
}