EOC strange behavoir on ADC STM32H563VGT6

[DAUSILI]

Hi,
I don't understand the behavior of EOC bit of ADC_ISR register at the end of conversion process.
My micro code is STM32H563VGT6.
I start from example "ADC_SingleConversion_TriggerSW_Init".
As the example I have to convert a single channel, single conversion mode.
This the problem:
after I start the conversion, the bit EOC and EOS go high togheter. 
But EOC then goes low, with no reset by software and any read of the register ADC_DR.
The DMA is not active.
Then when I loop with this condition:
while ( ! LL_ADC_IsActiveFlag_EOC() )
I stuck in the loop.
Why this behavior?
Thank you.

[TDK]

EOC is cleared when the debugger reads the DR register.