Tapping an iPhone is very hard; but as Pegasus showed, not impossible.
As a precaution, Settings --> Privacy & Security --> Lockdown Mode --> Turn on Lockdown Mode. Follow the instructions -- all of them. If this does not remedy your problem, it’s you.
One other thing: have you been to another country shortly before this began? The PRC comes to mind. I’ve read advice to take advice take a burner when take a burner when visiting the PRC. I believe it tries to tap into all foreign visitors phones.