Lost Device Claim Declined

Claim declined for lost device. I was having family gathering in my own home, I placed my phone in a charger in the lounge, phone got lost during the gathering and I couldn't find it. Blocked the device, got a case number from saps and sent it through to santam(Mtn claims), claim declined with the reason that I left the device "unattended whilst charging", on their policy documents nothing states that specific reason "Whilst Charging" only when I claim they telling me about "Unattended whilst charging"

I have been paying for loss or damage, device is lost now the loss is an issue. This is very unfair, we being ****** daily light on a sunny day