WhatsApp calls are logged as "Private number" although "Block private numbers" is enabled

[Davidus76]

Hello,
I would like to report what appears to be a reproducible issue.
Environment
Device: Samsung Galaxy A54
Android: Latest available version
Callfilter.app: Version 1.35.3 CH
Protection enabled
"Block private numbers" enabled
Description
Whenever I make or receive a WhatsApp voice call, Callfilter creates a new entry in the call history as "Private number".
At first, I thought I was receiving many anonymous phone calls. However, after investigating the issue, I believe these entries are actually generated by WhatsApp.
How I investigated
I compared the timestamps in:
Callfilter call history
Android Phone app call history
WhatsApp call history
Every "Private number" entry matched a WhatsApp call exactly.
To verify this, I deliberately repeated the test several times.
Result:
Incoming WhatsApp call → new "Private number" entry in Callfilter.
Outgoing WhatsApp call → new "Private number" entry in Callfilter.
The behaviour is fully reproducible.
Why I think this is a bug
I have enabled "Block private numbers".
If these were genuine anonymous GSM phone calls, Callfilter should block them.
Instead:
the WhatsApp call is completed normally,
nothing is actually blocked,
but Callfilter still creates a "Private number" entry.
This makes me think that Callfilter is interpreting Android ConnectionService/VoIP events from WhatsApp as anonymous phone calls.
Impact
This creates a misleading call history.
It appears as though I have received many anonymous phone calls, while in reality those entries correspond to WhatsApp calls.
This can also distort statistics and make users believe they are receiving hidden-number calls when they are not.
Suggestion
If possible, these events should either:
not be logged at all, or
be identified as WhatsApp/VoIP calls instead of Private number.
I can reproduce this every time on my device.
Has anyone else experienced the same behaviour?
Thank you for your work on Callfilter!

 

[admin]

Hello,
I would like to report what appears to be a reproducible issue.
Environment
Device: Samsung Galaxy A54
Android: Latest available version
Callfilter.app: Version 1.35.3 CH
Protection enabled
"Block private numbers" enabled
Description
Whenever I make or receive a WhatsApp voice call, Callfilter creates a new entry in the call history as "Private number".
At first, I thought I was receiving many anonymous phone calls. However, after investigating the issue, I believe these entries are actually generated by WhatsApp.
How I investigated
I compared the timestamps in:
Callfilter call history
Android Phone app call history
WhatsApp call history
Every "Private number" entry matched a WhatsApp call exactly.
To verify this, I deliberately repeated the test several times.
Result:
Incoming WhatsApp call → new "Private number" entry in Callfilter.
Outgoing WhatsApp call → new "Private number" entry in Callfilter.
The behaviour is fully reproducible.
Why I think this is a bug
I have enabled "Block private numbers".
If these were genuine anonymous GSM phone calls, Callfilter should block them.
Instead:
the WhatsApp call is completed normally,
nothing is actually blocked,
but Callfilter still creates a "Private number" entry.
This makes me think that Callfilter is interpreting Android ConnectionService/VoIP events from WhatsApp as anonymous phone calls.
Impact
This creates a misleading call history.
It appears as though I have received many anonymous phone calls, while in reality those entries correspond to WhatsApp calls.
This can also distort statistics and make users believe they are receiving hidden-number calls when they are not.
Suggestion
If possible, these events should either:
not be logged at all, or
be identified as WhatsApp/VoIP calls instead of Private number.
I can reproduce this every time on my device.
Has anyone else experienced the same behaviour?
Thank you for your work on Callfilter!

Hello,

Thank you very much for the detailed report. Yes, you are right — this is clearly a bug.

We have already received similar reports from a few users, but so far we have not been able to reproduce the issue on our own devices. It seems to appear only for a very small number of users, which makes it very difficult to catch and fix without help from someone who can reproduce it.

Would you be willing to join the beta testing program on Google Play?

This would help us a lot. We could prepare a test version with a possible fix, and you could check whether the problem is gone on your device.

To join the beta program:

1. Open Google Play.
2. Open the Callfilter.app page.
3. Scroll down to the “Join the beta” section.
4. Tap “Join”.
5. Wait a few minutes until Google Play updates your participation status.

After that, please write here that you have joined the beta program.

Since we cannot reproduce this bug ourselves yet, it may take more than one attempt. But with your help, it should be much easier to find and fix the cause.

 

[Davidus76]

I just joined the beta program

 

[Davidus76]

During the investigation, I initially suspected a Google Maps Bluetooth voice setting because years ago I had changed such a setting to fix truncated navigation announcements. I tested this by disabling the current Bluetooth voice option, but the behavior remained unchanged, so this hypothesis could not be confirmed.
One earlier observation may be relevant: even before installing Callfilter, WhatsApp calls were displayed as "Unknown" on my car's Bluetooth system.