DFRobot Mega2560 I2C Not Working

Hi all,
I noticed that my Mega board from DFRobot has a mulfunctioned I2C bus. The SDA is always LOW and SCL is always HIGH when no I2C devices are connected to the board. I tried the I2C scanner, but it was not able to detect the addresses of the devices connected to the bus. Can anyone suggest a solution to this? Or I should replace the board with a new one. Thanks.
I noticed that my Mega board from DFRobot has a mulfunctioned I2C bus. The SDA is always LOW and SCL is always HIGH when no I2C devices are connected to the board. I tried the I2C scanner, but it was not able to detect the addresses of the devices connected to the bus. Can anyone suggest a solution to this? Or I should replace the board with a new one. Thanks.