It's a big country; surely there's at least one instance running.

Mastodon gGmbH does not have an operating presence in Nepal - but it is not the whole of Mastodon (or the Fediverse) by any means!

I had a quick look at the maps I could find that indicated the locations of Mastodon server instances, and I was not able to find anything local to their - of course that's not to say there is not one or more. It is important to the network that there should be many Mastodon instances, in many places, so it would be great if there were some!