Some time last year I tried to transfer it from 1and1 to Gandi, but it seems to have got stuck in limbo.
The WHOIS records show that Gandi have it, but it doesn't appear in my account on Gandi.
Now what I'm seeing is that the domain expired on 17th of June, and Gandi seem to have removed my nameserver glue record on 17th of July (2 days ago).
As a result of this, my website and email are now both unavailable, including the email address that Gandi have on file for me.
Gandi's support form allows you to specify an alternative email address, which I have done, but so far I'm not getting a reply from them.
I called the only phone number I could find for Gandi, but it just directs you to use the online form and there is no way to reach a human.
What is the fastest way to get my domain name back?
I wouldn't normally recommend it immediately, but it really looks like they try to hide any interactive support channel.
Nominet explained to me how I can transfer the domain out of Gandi and into another registrar without Gandi's assistance. I am now trying to transfer it to Namecheap.