Ads and reward behavior

Hi.
Pretty new to brave (a month and half). So far so good except the ads not counting recently but it’s on is way to be fixed.
I have several questions regarding ads and reward system and I’m sorry if those have already be asked.
Firstly, I want to say that I don’t check my reward every time I open an ad, only from time to time but some things bothering me so here we go
1/ to be count, do we have to watch an ad for some time (x seconds)?
2/ is there any delay between opening 2 different ads (It look like if I open 2 ads one after the second, the later isn’t count)
3/ what if I open two ads from the same provider one after the other? Does it count as 2 ads or one (it seems that it’s only one but I may be wrong)

Regards

Edit : Brave on three system Android 7, Android 10 and windows 10. All brave apps are up to date

The answer is 1. The notification is the ads. You get paid for watching/seeing the ads – the notification. https://support.brave.com/hc/en-us/sections/360004119132-Brave-Ads

Well… I guess I should I’ve read FAQs before…
Thanks for the heads-up
Regards