Hi, Maybe you have some firewall or something blocking your copy of Unity from accessing the servers? Try disabling your Windows firewall temporarily, and whatever else you have installed. But since you did not provide any details, I'll ask does this happen to every item in Package Manager or just for that specific Asset Store Tools? P.S. have you ever thought what happens when too many people title their posts "Help" or such. It would be more beneficial for this forum if this post had a more descriptive title, like "My Unity <version here> cannot access <package name here> via Package Manager" or something better.
I disabled everything I needed, but it's still the same thing. Yes, this happens with every package. 4 Days already this stuff