Q: Ive a lot of unauthorized charges. I how I dispute this ???

They show on your account's purchase history (or family members if you are a family organiser in family sharing), and nobody else has access to your account or devices/computers ? If they do show on your account, and nobody has access to it, then contact iTunes Support : https://support.apple.com/contact  . And change your account's password http://appleid.apple.com - after changing it : What to do after you change your Apple ID email address or password - Apple Support.

If they don't show on your (or family member) accounts contact your card issuer.