This has nothing to do with InDesign and is well known scam. Delete the email and be done with it.
Apologies, wasn't sure which section to post the question in.
OK, thanks for the response.
You do have to be careful that your domain doesn't expire—you have to pay the yearly fee or it will be available to anyone. If you've lost track of where it's registered or when it expires, you can look it up here:
Luckily it is on auto renewal, so will be OK.