Not flashing scatch on Arduino UNO board

Hi all,
I have problem. My scatch is ready and I compilate without errors, but when I try to upload I have fails:
Arduino: 1.8.6 (Windows 10), Board: "Arduino/Genuino Uno"

Sketch uses 2838 bytes (8%) of program storage space. Maximum is 32256 bytes.
Global variables use 368 bytes (17%) of dynamic memory, leaving 1680 bytes for local variables. Maximum is 2048 bytes.
C:\Program Files (x86)\Arduino\hardware\tools\avr/bin/avrdude -CC:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf -v -patmega328p -carduino -PCOM6 -b115200 -D -Uflash:w:C:\Users\npeshev\AppData\Local\Temp\arduino_build_228832/ODU_short_test.ino.hex:i

avrdude: Version 6.3-20171130
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch

System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf"

Using Port : COM6
Using Programmer : arduino
Overriding Baud Rate : 115200
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x30
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x20
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x30
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x20
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x30
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x20
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x30
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x20
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x30
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x20

avrdude done. Thank you.

An error occurred while uploading the sketch

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

I checked "upload" check box from File-> Preferences and Adruino Uno and COM6(adruino port) but without success and Programmer:AVR ISP.
Where is the possible problem?

Remove any connections to pins 0 and 1 on your Arduino board. These pins are used for communication with your computer, including uploads. Connecting anything to these pins can interfere with uploads.

Make sure you have the correct board selected from the Tools > Board menu.

Make sure you have selected the port of your Arduino board from the Tools > Port menu.

Sometimes the port will be labeled with the board name in the menu. Other times it will not. If you don’t know which port is your Arduino, you can find it like this:

  • Unplug your Arduino board from the computer.
  • Tools > Port
  • Note the ports, if any, listed in the menu.
  • Close the Tools menu. The ports list is only updated when the Tools menu is re-opened, so this step is essential.
  • Plug your Arduino board into the computer.
  • Tools > Port - The new port listed in the menu is your Arduino board.

neo_nedo:
and Programmer:AVR ISP.

Note that the Tools > Programmer menu selection is only used when you are doing Tools > Burn Bootloader or Sketch > Upload Using Programmer. When you are doing a standard upload, the Tools > Programmer menu selection is completely ignored, so it doesn’t matter what you have it set to.