I’m probably the least tech savvie person on here but I can relate to your situation. I got my devices wiped and reset. I never use them for anything important or keep anything stored on them. If its not spyware then assume that we are all being spied on/tracked for our data regardless. In my experience, tech companies say there are no issues and imply you are paranoid. Best advice I got was to keep handwritten notes of anything out of the ordinary so you have a timeline at least, and/or take photos with a digital camera (not smart device) rather than screen shots of anything unusual you notice on your device should you need proof. Context - I was stalked by an ex.