Adding new website problem (Invalid format of Url alias: sv")

Hi

I’m in the process of adding a B2C site to an existing B2B. The B2B site has a number of different websites with different languages, such as /sv, /da etc.
But it appears I’m unable to use /sv for the new site, even though the domain differs. When I enter something like domain2 .com/sv I’m getting “Ett fel inträffade Invalid format of Url alias: sv”.

It did work when I changed the other configuration from domain1.com/sv to something else, so is there a limitation here? despite the domain name being different?
The domain1 .com/sv was the default website, but even when setting another website as the default, it doesn’t allow them both to co-exist.

It’s very strange because there were no problems having both domain1 .com/da and domain2 .com/da.

Are there limitations in place here? Or am I missing something?

Litium version: 6.1.1

Update: we changed this setting directly in the database instead and it seems to work correctly so far.