Simple. Factory reset your phone. I do not care if you have 500 baby pictures of your children on there. Just do a backup then factory reset. Keep your cell phone as basic as possible for a while. Keep phone with you at all times no matter what.
Next use a passcode to get into your phone use a 8 digit and not a 4 digit passcode.
Good impossible numbers to use is sometimes we remember a phone number from your childhood that other loved ones would not know about.
But now I would assume other things but that is not my place and only concern is data safety.
After you have done the above next step if you use a pc at work reset all your account passwords. Resetting passwords at home just means the home pc has a keylogger and defeats the attempt of resetting passwords.
After doing the above you can slow add back all the apps on the phone you use.
You need a new router made for higher bandwidth. No router $140 and cheaper can offer decent I/o