Oppo
Sort Contacts by First or Last Name auf Oppo
Contacts on Oppo phones display in one consistent order across Calls, Messages, and the dialer. That order is controlled by a single setting inside the Contacts app, not by how individual entries were saved or imported.
If names look inconsistent, some starting with a first name, others with a surname, the sorting rule usually does not match how the underlying data was entered. Switching the sort field realigns the display without changing any actual contact data.
Where to change it
Open Tap on Contacts ➔ Open the Menu ➔ Tap on Settings ➔ Tap on Sort by ➔ Choose First name or Last name. The change applies immediately and affects the entire contact list, not just individual entries.
This fix works when the whole list feels inconsistent. If only a handful of contacts look wrong, the issue is more likely in how those specific entries were saved, for example a full name typed into the first-name field. In that case, editing the affected contacts directly is faster than changing the global sort order.
Side effect: switching the sort field also changes how names are grouped under letter headers in the alphabet index, since that index follows the same setting.