URL     = "https://b24-ar17wx.bitrix24.by/rest/1/yg2...";
    FieldID = "255";

    Result = OPI_Bitrix24.DeleteCustomTaskField(URL, FieldID);

    URL     = "b24-ar17wx.bitrix24.by";
    Token   = "7afc3e67006e9f06006b12e400000001000...";
    FieldID = "257";

    Result = OPI_Bitrix24.DeleteCustomTaskField(URL, FieldID, Token);