Previously I have posted about my phone being reported as line busy when it wasn’t. Have now found that family member’s mobile number in my contacts was being blacklisted by phone blocker app, Known Calls:
I have uninstalled the app and now any family member that calls is identified as unknown caller. How do I solve this?
Fairphone 3+, not rooted,
/e/ OS: 2.5-t-20241111446629-official-FP3
Regain your privacy! Adopt /e/OS the deGoogled mobile OS and online services
Anyone help with this?
OK. Having done some research this is a carrier issue. The helpdesk of carrier is requesting ICCID on back of SIM. Is this a normal request or suspicious?
I would say that this indicated that the carrier is taking your case seriously. I had to look up the significance of ICCID, the Integrated Circuit Card Identification number, the carrier will use the ICCID to identify the correct network to connect your device, authenticate it, and ensure you get the right services.
This link indicates the detail of how your carrier (or Mobile Network Operator, MNO) uses the ICCID.
Here is what Google support said about a similar issue to yours All incoming calls listed as "unknown" in phone app - Google Phone app Community
Known Calls has a contact page Contact us – FelenaSoft Company – software development and outsourcing – Felenasoft, maybe they can help with troubleshooting.
Thanks for replying, appreciate your input.
Well guess what the request for ICCID is no longer showing. Now putting onus back on manufacturer. Beginning to wonder about changing to Smarty.
Been advised to reset network settings, now back to number engaged when anyone tries to contact me.
The problem is clearly a handset issue. I put Smarty Sim in old 1+ 3T and I can receive calls, was going straight to voicemail in Fairphone 3+. This means, annoyingly, I may have to purchase a new phone when the whole purpose of owning a Fairphone was not having to upgrade at all. Very disappointed. This means I will have to look at a new phone that allows a data sim to be included! 
UPDATE: deleted call blocker and now working! Why is it so hard to get a decent call blocker application!
