You need connection details from whatever wallet you are using with your custom domain.
Discussion
What does that mean? Any links to such info?
What service/app are you trying to use to operate your custom Ln address?
I wanna be able to use my custom domain with my nostr:npub1getal6ykt05fsz5nqu4uld09nfj3y3qxmv8crys4aeut53unfvlqr80nfm wallet
Ok, I don't think they support it directly so you will probably need to use another service/open source application first then link that to your Alby.