I think my account has been hacked. What should I do?

Follow the instructions listed in: If you think your Apple ID has been compromised - Apple Support

After changing your password, follow the advice listed in: What to do after you change your Apple ID or password - Apple Support

Toads1204 Said:

"I think my account has been hacked.: What should I do? My account has been hacked"

Being that you Apple Account seems of high0concern here, most certain consider the following:

• Modifying: your login credentials (Using Both a New eMail and a New Password)
• Associating: a different method of payment to your account
• Enabling: Two-Factor Authentication for Apple ID and for all other accounts that have such an available option