I think my phone has been hacked

Because there are not active exploits for an iPhone that has not been jailbroken.

If you believe one or more of your accounts were compromised, change your passwords and turn on 2 factor authentication wherever available.

Why do you think that?

If it isn't jailbroken, then it hasn't been 'hacked' or 'compromised'.

It's possible one or more of your online accounts were compromised, but the phone itself wasn't.

What are the problems?