URL    = "https://b24-ar17wx.bitrix24.by/rest/1/yg2...";
    TaskID = "3216";
    FileID = "17290";

    Result = OPI_Bitrix24.AttachFileToTopic(URL, TaskID, FileID);

    URL    = "b24-ar17wx.bitrix24.by";
    Token  = "48573267006e9f06006b12e400000001000...";
    TaskID = "3218";

    Result = OPI_Bitrix24.AttachFileToTopic(URL, TaskID, FileID, Token);