I am still livid on a weekly basis when some strangers create an account for a service using my email address (non-maliciously, usually); I get a "verification" email; and I can only choose "YES, Please verify", or ignore at my peril. From tiny little mom-and-pop shops, to FAANG giants, nobody is giving me the opportunity to say "NO that's NOT me!". And though it's a "verification" email, typically account is usable…
Given it is your email that is being used, that should allow for you to take over the account(s)? I'd submit a password reset, change the password, then just allow the account to live a dormant life. That of course doesn't make it any less annoying, but it would at least stop an actor from using an account that is associated to your email.
The only mechanism you have to alert the person usurping your email identity that there is an issue is to trigger the phone call verification 3 times per day, preferably around 4am.
If you call the phone support, it will give you robots until playing a pre-recorded message telling you to physically mail a legal request including copies of your ID etc.