I have nano connected with two momentary buttons and 2 relay module.
I programmed it , when the button 1 is pressed to switch on relay 1, delay some time and going back off and same for button 2 and relay 2. So far, so good it is work.
The main goal is never to have both relays switched on in the same time and my code work fine.
The problem is, that if the power is lost for very short time and nano is restarting , during this process on some check (i don't know what check) it switch on both relays in same time for short time, which is my issue. I have to avoid that.
If the power is out for more than 2-3 second and nano boot again - this problem is not persist.