You could try & see about changing your Apple ID's 'password' just in case someone had guessed yours.
• Change your Apple ID password - Apple Support
https://support.apple.com/en-us/HT201355
Unless you acquired an iDevice second-hand where an original owner still had control over 'their' device
the issue should only require you to act on the privacy settings in your own account via Apple ID site
and within any Apple product you have. (If this were so, you'd be unable to update the iOS, etc.)
If you use a PC or Mac, you can also access your Apple ID account from either to check and change settings.
And if you've forgotten your Apple ID you can see about accessing your iOS device here:
• Change your Apple ID password - Apple Support
https://support.apple.com/en-us/HT201487
• Security and your Apple ID - Apple Support
https://support.apple.com/en-us/HT201303
Login to Apple ID to manage your Account:
https://appleid.apple.com/
Not sure at what point your issue began, and you may need to see
if an Apple expert or authorized sales/support person could help.
Genius Bar Reservation and Apple Support Options - Apple
https://www.apple.com/retail/geniusbar/
Good luck & happy trails! 😊
