You can’t use this instance username to login to a different instance. You need to be on Beehaw.org, to use your Beehaw account; you can’t use that to logon to kbin.social. However, you should be able to see the instance and subscribe to it from Beehaw:

Search for the URL

Click the resulting link

Click subscribe.

Just to double check, are you trying to login with your beehaw account on the kbin website or trying to find the community through beehaw.org?

The reason I am asking is because accounts aren’t transferring to other instances. It works the other way around, through your fediverse instance (in this case beehaw) you can access other federated instances and communities.

Normally, you should be able to go here and find other communities of instances that beehaw has been federated with. Or you can access them directly as well.

Having said that, I couldn’t find the specific instance through search and the direct url (https://beehaw.org/c/[email protected]) also doesn’t seem to work. This might have something to do with the character length of the community.