My other Apple ID account password was changed

https://support.apple.com/en-us/HT204145

Enter the Apple (iCloud) ID, and click Forgot Password. See if you can get a Rescue or Notification  email option if necessary.

Apple ID - Manage            

Apple ID – Forgot Password            

You might want to consider changing your password and making sure it is a strong one. You can also add 2 Factor Authentication to your account for more security. If the attempts continue, you might want to consider a name change.

 Apple ID Password Change.     

Note the restrictions in the article.

Apple ID Name Change.        

 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.

Apple ID -Two-factor authentication          

Two Factor Authentification availability.    

2 Factor Authentication - How to generate a recovery key

Apple ID - Using app-specific passwords.     

Apple ID - Two Step Verifications FAQ