STM32F4 I2C EV6 stuck - stm32f4discovery

Question

I'm working on my final year project, and i'm using STM32F4 discovery to communicate with an altitude sensor via I2C. I'm using USART to check my code and locate where it stucks and i found that it blocks at while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));. I saw that many persons have the same problem on the internet but no solution worked. Any suggestion?
Here is the code:
uint8_t Read_IIC2(uint8_t SlaveAddress, uint8_t REG_Address)
{
uint8_t REG_data;
while(I2C_GetFlagStatus(I2C2, I2C_FLAG_BUSY));
I2C_AcknowledgeConfig(I2C2, DISABLE);
I2C_GenerateSTART(I2C2,ENABLE);
while(!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT));
I2C_Send7bitAddress(I2C2,SlaveAddress<<1,I2C_Direction_Transmitter);
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
uart_conf();
USART_puts(USART1, "rread\n\r");
I2C_SendData(I2C2,REG_Address);
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
I2C_GenerateSTART(I2C2,ENABLE);
while(!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT));
I2C_Send7bitAddress(I2C2,SlaveAddress,I2C_Direction_Receiver);
while(!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
while(I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_RECEIVED));
REG_data = I2C_ReceiveData (I2C2);
return REG_data;
}
void I2C_Configuration(void)
{
GPIO_InitTypeDef GPIO_InitStruct;
I2C_InitTypeDef I2C_InitStruct;
// enable APB1 peripheral clock for I2C2
RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C2, ENABLE);
// enable clock for SCL and SDA pins
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
/* setup SCL and SDA pins
* You can connect I2C2 to two different
* pairs of pins:
* 1. SCL on PB6 and SDA on PB7
* 2. SCL on PB8 and SDA on PB9
*/
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_11; // we are going to use PB6 and PB7
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF; // set pins to alternate function
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz; // set GPIO speed
GPIO_InitStruct.GPIO_OType = GPIO_OType_OD; // set output to open drain --> the line has to be only pulled low, not driven high
GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP; // enable pull up resistors
GPIO_Init(GPIOB, &GPIO_InitStruct); // init GPIOB
// Connect I2C2 pins to AF
GPIO_PinAFConfig(GPIOB, GPIO_PinSource10, GPIO_AF_I2C2); // SCL
GPIO_PinAFConfig(GPIOB, GPIO_PinSource11, GPIO_AF_I2C2); // SDA
// configure I2C2
I2C_InitStruct.I2C_ClockSpeed = 400000; // 100kHz
I2C_InitStruct.I2C_Mode = I2C_Mode_I2C; // I2C mode
I2C_InitStruct.I2C_DutyCycle = I2C_DutyCycle_2; // 50% duty cycle --> standard
I2C_InitStruct.I2C_OwnAddress1 = 0x00; // own address, not relevant in master mode
I2C_InitStruct.I2C_Ack = I2C_Ack_Disable; // disable acknowledge when reading (can be changed later on)
I2C_InitStruct.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit; // set address length to 7 bit addresses
I2C_Init(I2C2, &I2C_InitStruct); // init I2C2
// enable I2C2
I2C_Cmd(I2C2, ENABLE);
}