Dude, if what you say is true, enable airplane mode immediately. I would not try to do a fresh backup or anything. It would be best to restore from one before the hack but who knows when that was. Getting that info is incredibly challenging and to be honest, this is something better handled in person with a professional. I am a Microsoft / Cisco guy so I can't really help.
Advice for you, closely monitor any account that has financial spending abilities like Amazon, invest apps, PayPal, and of course your bank as well. Do you have a computer with any symptoms? In short you will need to systematically reset most if not all of your passwords, home network devices, your hacked devices. You literally will have to factory reset EVERYTHING but in a specific order because if there are key loggers you could go through the whole process and still end up at square one.
Once you start this process you have to move FAST. I highly recommend going to a friends house and using their internet. Do not start any of this until you have become familiar with the steps. If the person has a key logger or other monitoring app on your phone then he has the ability to get the wifi password, connect to it, and start attacking other devices. You may be luckily but its so hard to tell.
With the phone in airplane mode, as well as any other computer (pc / mac), mobile device, anything that connects to the home internet that you feel may be at risk, factory reset your home router and the phone. Get the phone up and running using cellular data. I genuinely do not know if restoring from your backups is the kiss of death or no big deal. You will find out though.
Use your phone to setup your new home wifi or if necessary, a computer. Keep the computer's wifi disabled and use ethernet. Immediately begin reseting all your passwords starting with the email accounts you use to receive alerts from your most important financial accounts. If you don't use MFA, start now. After that I guess you wait and see. I still think this is serious enough to stop, grab some money, and go see someone in person that is qualified. Oh, once you start resetting passwords you can use wifi again. If the person is really good it wont take long for you to know. Best of luck to you. I have seen this happen first hand and it is no fun.