All my Apple Devices are hacked !!!

I've been struggling with a persistent Malware that has hacked all my Apple devices (iPhone & Mac), the problem started when I was traveling and had to connect to a public WIFI, my iPhone was affected at first all passwords were changed and it was unavailable for 2 weeks! had to take it to an apple store where they factory earned everything and it was all good again until last month when I noticed there was more than 20 devices connected to my home router and the internet started to become very slow and lags a lot. and also once noticed that my camera green light was on while my iPhone was locked. which scared me a bit i thought I left one of the applications with the permission to camera working in the background and when I checked there wasn't any apps there! so had to do a little bit of digging myself through the internet and Mac and using terminal I have figured that there was 4 other IPs connected to both of my devices and found some suspicious files named after (Ads, Malware, Scams) and multiple copies of original Mac files that keeps multiplying themselves every time I delete them, it just seems like an endless loop of trying to get rid of this malicious malware. p.s. all my devices are updated with the latest IOS systems, I have never jailbroken any of them, used to download some stuff from safe websites on my Mac for study purposes, however I'm not sure if I might got them from there or not. Need good suggestions to get rid of it ASAP antivirus software,... anything that might have worked with you before, I have manufacture erased both of my devices however the files keeps coming back, contacted apple support they were astonished when I told them that I found malicious files on y Mac when it successfully passed there test of safety. The malicious files are hidden under software languages files and genuine iOS files so it might be hard to figure out for some tests.

PLEASE help with any tips or solutions to save my devices.