Got an Apple Support email with case number, didn’t contact them or ask for help

Idk what to do, just now seeing my email from 2 weeks ago and it was from Apple with a case number. For my phone and iPad I use an email no one knows about, so it caught me off guard. Called Apple and they can’t pull up the case number. I had an iPad stolen almost 2 years ago and believe my old ID was that email. And maybe my old phones, which I have but haven’t used one of them since summer and 2016. And old laptop that broke in September. The representative said if someone was trying to get support and they can’t show proof of purchase, the device will become a dummy one. And I think the iPad was reported as stolen. I’m just worried cause my ex had access to this account a year ago, I changed the password, but my location was tracking on the other devices (he set up without me knowing) idk about the laptop tho. I should be fine with my new devices, but I’m just worried as I don’t want him to know where I’m at and it freaks me out