FNB Connect is refusing to blacklist my phone

I have been an FNB connect client for years, on the 19th June 2022 I lost my phone and I have been tryingto have the phone blacklisted by FN Connect to no avail. I am being sent from pillar to post and I am told that FN Connect cannot blacklist the phone because someone inserted another sim card! My insurance will not pay until I get a ITC number from FNB Connect and they are refusing to assist me! This is i really frustrating me because my insurance insists that FNB Connect needs to blacklist the phone!