Wrong data on UART2

Hi,

I have an STTM32F103C8 MCU ("Blue pill") board. What I write to UART1 goes well to he PC. But if I try send data over UART2 only some of the sent characers appear on the PC.

You can see he code below. Is there anyone who knows, what is wrong?

Thanks!

#include "stm32f10x.h"

/* function prototypes */
void RCC_Configuration(void);
void GPIO_Configuration(void);
void USART_Configuration(USART_TypeDef* USARTx);
void SysTick_Handler(void);
void USART_Send_Char(USART_TypeDef* USARTx, char cData);
void USART_Send_CharArray(USART_TypeDef* USARTx, char* Buffer);
void USART_Send_Number(USART_TypeDef* USARTx, uint32_t x);

int iTick = 0;

void delay_us(long usecs);

int main(void)
{
    char data;
          int j=0;
                char* RXBUFF="testmessage\0";
                char* TXBUFF;

    SystemInit();
    RCC_Configuration();
    //NVIC_Configuration();
    GPIO_Configuration();
    USART_Configuration(USART2);
                USART_Configuration(USART1);
    //TIM2_Configuration();

    // Init SysTick Timer
    SysTick_Config(1000000);

    while(1)
    {
                                                delay_us(5000);
                                                USART_Send_CharArray(USART1,RXBUFF);
                                                USART_Send_Number(USART1,123);
                                                delay_us(5000);
                                                USART_Send_CharArray(USART2,RXBUFF);
                                                USART_Send_Number(USART2,123456789);
    }
}

void RCC_Configuration(void)
{
    // Enable GPIOA, GPIOB clock
    RCC_APB2PeriphClockCmd (RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO , ENABLE);
    // Enable USARTx clock
                RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1 , ENABLE);
                RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);
}

void  SysTick_Handler(void)
{
    iTick = 1;
}

void GPIO_Configuration(void)
{
    // Initialize Leds mounted on STM32 board
    GPIO_InitTypeDef  GPIO_InitStructure;

    // Configure the GPIO_LED pin
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOC, &GPIO_InitStructure);

    // Configure USART1 Rx (PA10) as input
    GPIO_InitStructure.GPIO_Pin   = GPIO_Pin_10 | GPIO_Pin_3;
    GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    // Configure USART1 Tx (PA9) as alternate function
    GPIO_InitStructure.GPIO_Pin   = GPIO_Pin_9 | GPIO_Pin_2;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_AF_PP;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
}

void USART_Configuration(USART_TypeDef* USARTx)
{
    USART_InitTypeDef USART_InitStructure;

    /* USART1 configured as follow:
          - BaudRate = 115200 baud
          - Word Length = 8 Bits
          - One Stop Bit
          - No parity
          - Hardware flow control disabled (RTS and CTS signals)
          - Receive and transmit enabled
    */
    USART_InitStructure.USART_BaudRate            = 115200;
    USART_InitStructure.USART_WordLength          = USART_WordLength_8b;
    USART_InitStructure.USART_StopBits            = USART_StopBits_1;
    USART_InitStructure.USART_Parity              = USART_Parity_No ;
    USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_InitStructure.USART_Mode                = USART_Mode_Rx | USART_Mode_Tx;
    USART_Init(USARTx, &USART_InitStructure);

    USART_Cmd(USARTx, ENABLE);
}

void USART_Send_Char(USART_TypeDef* USARTx, char cData)
{
    while(USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
    USART_SendData(USARTx, cData);
}

void USART_Send_CharArray(USART_TypeDef* USARTx, char Buffer[]) {
        int i=0;
        while (Buffer[i]) {
                while(USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
                USART_SendData(USARTx,Buffer[i++]);
        }
}

void USART_Send_String(USART_TypeDef* USARTx, const char *str)
{
    while (*str)
    {
        while(USART_GetFlagStatus(USARTx, USART_FLAG_TXE) == RESET);
        USART_SendData(USARTx, *str++);
    }
}

void USART_Send_Number(USART_TypeDef* USARTx, uint32_t x)
{
  char value[10]; //a temp array to hold results of conversion
  int i = 0; //loop index

  do
  {
    value[i++] = (char)(x % 10) + '0'; //convert integer to character
    x /= 10;
  } while(x);

  while(i) //send data
  {
    USART_Send_Char(USARTx, value[--i]);
  }
}

void delay_us(long usecs) {
        long i,j;
        for (i=0;i++ < usecs;) {
                for (j=0;j++ < 0x12;) {
                ;}
        }
}