Google Analytics shows average visit duration 0:00 from certain countries only

That’s my website, with a blog:

I’ve noticed that on google analytics, on the geo reports, I get 0:00 for the average visit duration but only for certain countries: USA and Canada.

Could that indicate a problem with the server? or something blocking users from these countries to access my site?

Thank you,

Here are some more details about the visiting stats from the USA:

I Googled that for you and got these:

Thank you sdayman,
I already found that post on stackoverflow, but I don’t think it’s the same issue.
In my case, as you can see in the screenshots I’ve added, the 0:00 visit duration is the majority visit time of visitors from the USA and Canada, unlike the rest of the visitors on the site.
It seems weird, and related to the origin of the visits as if there is a problem with the local server or something.
Is there a way to check if the there’s no problem visiting my site from these countries?