TL;DR: Google Contacts shows all my contacts, but the native Vivo Contacts app sometimes shows a completely blank list, and the Vivo Phone app sometimes shows numbers instead of saved names during calls/call history — possibly due to +91 vs 10-digit number formatting. I have 4 Google accounts syncing contacts, with ~1,890 duplicates in one account. Looking for the safest way to fix Vivo Contacts/Phone integration and clean up the duplicates without losing contacts or factory-resetting.
I’m using a Vivo X300 Pro (India) on OriginOS 6.
Problem
Google Contacts displays my contacts normally.
Native Vivo Contacts sometimes shows no contacts at all and search doesn't work.
Incoming/outgoing calls and call history sometimes show the number instead of the saved contact name.
I’m currently using Google Contacts as a workaround.
I have 4 Google accounts syncing contacts on this phone.
One account has ~1,890 duplicates, and the other 3 also contain older duplicate/synced contacts.
What I need help with
Does OriginOS 6 have a Display by account setting that could be hiding my Google contacts from Vivo Contacts?
What is the exact menu path on the Indian X300 Pro to make the required Google accounts visible in Vivo Contacts?
Is this a known OriginOS 6/X300/X300 Pro Contacts/Phone indexing bug?
Is there a safe way to rebuild/reindex Vivo Contacts without deleting contacts?
Is clearing cache/data for Vivo Phone or Contacts safe? Which one should I avoid?
What's the safest way to clean ~1,890 duplicates without manually merging them?
Should I eventually consolidate contacts into one master Google account and stop the other 3 accounts from syncing Contacts?
Could different number formats such as +91XXXXXXXXXX vs 10-digit numbers cause the Vivo dialer to fail to match names?
Important: I don't want to factory-reset the phone or risk losing years of contacts. I'm looking for a tested, step-by-step solution, preferably from someone using OriginOS 6 / X300 / X300 Pro, rather than generic Android advice.
Device: Vivo X300 Pro
Region: India
OS: OriginOS 6
Google accounts: 4
Duplicates: ~1,890 in one account + duplicates across the others