I got a new phone and old contacts appeared on Google's stock Phone App. If I delete them, they reappear after I restart the phone. They do not appear on Google's stock Contacts app.
Contact sync is off; I also tried turning it back on again to no avail. I have cleared both cache and data from every app with "contacts" or "phone" in the name (I did not install any, this is a brand new phone).
I installed the "Simple Contacts" app from F-Droid and it shows these contacts as SIM contacts. I have tried deleting them using this app, to no avail. I have cleared data and cache from the "SimContacts" system app, to no avail. This is an ASUS Zenphone Max Pro, ASUS_X00TDB, Android version 8.1.0, all apps up to date.
Is there any way I can permanently delete these contacts? I have looked for SIM card editing apps but found none that were ad-free. I do not mind paying for the app.