did you contact your hossting provider about this?
it’s called a wildcard domain, where the https://domain.com/ resolves to https://www.domain.com.
technically, all websites ‘are’ at www. you may know all this already, and i’m no expert at it, but…
there’s https://ftp.domain.com to serve file transfers
and gopher.domain.com to serve gopher, etc etc
and https://www.domain.com to serve web pages.
but people choose to remove the www… so they have something called a ‘wildcard’ DNS. but your hosting provider may be using redirects instead.
well i’m not explaining it very well. but i think this is something to check with your hosting provider.
and i don’t think it will cause you any trouble in terms of search engine rankings… but not sure. did you read that somewhere?