AVRDUDE ERROR. PLEASE HELP

Hello everyone
Im trying upload blink led code but i cant.

When im try upload project, this message shows

avrdude: verification error, first mismatch at byte 0x0399
0x0f != 0x93
avrdude: verification error; content mismatch

Anyone can help me? :((
(R3 UNO)

(Sorry for my English :()