Shared Apple id

Check your device list to see if there is a device signed in that you don't recognize. You can remove the device using the steps in the article below. As a precaution, change your password.

Apple ID device list -Check to see where you‘re signed in.   * 

 Apple ID Password Change.   -  

ASC YouTube for How to reset your Apple ID password

 What to do after you change your Apple ID or password - Apple Support  -   I suggest doing this before you change your Apple ID or password.

Check Settings> your name and see if you recognize all your devices listed there

Furthermore, see this link and follow the instructions provided when you have suspicions that your Apple ID is compromised

If you think your Apple ID has been compromised - Apple Support