I have received emails that say my apple account was accessed in a different time zone, one that is in Europe. I changed my password and received another email that said it had been accessed again. What do I do?

I no longer have an iPhone. Tonight I have been twice notified my account has been accessed from a European time zone. I changed my password a d was again notified of this. I checked for devices and closed it the first time. It said the phone I had had accessed it. So I shut it down. The second time it said that it had been accessed there was no devices listed. What is going on?