Website not accessible in certain countries

Hey there,
I was a bit astonished, when a seller here told me that he cantc access my website from India. My traffic plummeted a bit since a few days without visible reasons. So I checked the accessibility with the help of https://asm.ca.com/en/ping.php and it showed that my site can't be accessed from Brazil, New Delhi India, and Manchester in the UK. I have my domain on namecheap and connected it to my web host via DNS.
Has anyone a clue why this is happening? Could a user from Manchester or New Delhi check if it works from your end?

Only your web hosting provider can tell you more about it.
It could be a country block set in the firewall following an attack, or it could be a peering issue. But giving the countries mentioned they are quite spread and it sounds unlikely since they would take quite different "internet roads". Either way the best way would be to contact them directly.

Thank you very much for your reply