iPhone name change

If your phone had a common name (such as “iphone”) and another device with the same name shares your Apple ID or is authorized in Find My iOS will change the name of one of the devices to differentiate them, by adding “(2)” or a higher number after the name. You can (and should) go to Settings/General/About and change to a unique name.

Go to settings then “ general “ “ About” after that press on “ Name “ and change the name that you want

There is nothing to be suspicious about the name change at all. Change it at will.