Question regarding UART_WaitOnFlagUntilTimeout

I am studying with the STM32F103RB, and there’s something I don’t understand.

In the function below, I noticed that it checks for an overrun in UART after confirming that the RXNE flag is 0 (which means there is no data to receive in the RDR). I think this is strange because an overrun should occur when RXNE is set.

Is there something that I misunderstood?

// below function was called with this : UART_WaitOnFlagUntilTimeout(huart, UART_FLAG_RXNE, RESET, tickstart, Timeout) != HAL_OK)

static HAL_StatusTypeDef UART_WaitOnFlagUntilTimeout(UART_HandleTypeDef *huart, uint32_t Flag, FlagStatus Status,
                                                     uint32_t Tickstart, uint32_t Timeout)
{
  /* Wait until flag is set */
  while ((__HAL_UART_GET_FLAG(huart, Flag) ? SET : RESET) == Status)
  {
    /* Check for the Timeout */
    if (Timeout != HAL_MAX_DELAY)
    {
      if (((HAL_GetTick() - Tickstart) > Timeout) || (Timeout == 0U))
      {

        return HAL_TIMEOUT;
      }

      if ((READ_BIT(huart->Instance->CR1, USART_CR1_RE) != 0U) && (Flag != UART_FLAG_TXE) && (Flag != UART_FLAG_TC))
      {
        if (__HAL_UART_GET_FLAG(huart, UART_FLAG_ORE) == SET)
        {
          /* Clear Overrun Error flag*/
          __HAL_UART_CLEAR_OREFLAG(huart);

          /* Blocking error : transfer is aborted
          Set the UART state ready to be able to start again the process,
          Disable Rx Interrupts if ongoing */
          UART_EndRxTransfer(huart);

          huart->ErrorCode = HAL_UART_ERROR_ORE;

          /* Process Unlocked */
          __HAL_UNLOCK(huart);

          return HAL_ERROR;
        }
      }
    }
  }
  return HAL_OK;
}

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