Apple ID and passwords

Apple ID accounts are independent of any hardware they’re used on and each one has a separate password.

Why are there multiple IDs on your device? Each person should have only one Apple ID and a device can be logged in with only one ID at a time.

The only “hacking” of Apple IDs that I’m aware of is if someone can guess the password. 2FA makes Apple IDs even more secure, but that obviously makes it more complicated when the user forgets their credentials.

Anyway, I would suggest selecting the Apple ID that has the most purchases made from that account, settling on that one, and stop using the rest.

In the future, if you forget your password, it’s better to reset it than to create a new account.

Reset your password here.  

What to do after you change your Apple ID or password - Apple Support

https://support.apple.com/en-us/HT204071

Recognize and avoid phishing messages, phony support calls, and other scams (Apple article):

http://support.apple.com/kb/HT4933

You can try setting up Family Sharing between the IDs if you want to be able to share purchases made with the IDs.

Family Sharing.         

Family Sharing - Set up.