Un wanted emails & phone numbers are added to my address book. Why is un authorized contacts being added to my address book? All un wanted email and conts, are automatically being added to my address book?

I'm experiencing issues with unwanted emails also containing strange, lengthy shipping addresses like DHL, UPS etc. or general contacts from retailers, un familiar un wanted phone numbers email address or websites. Somehow, phone numbers and email addresses are automatically being added to my address book without my authorization. This problem emerged after a recent update. Can you guide me on finding a settings option to resolve this issue? Your assistance would be greatly appreciated. Please help?

Ps I just use iPhone contacts in phone.