The ownership of the second phone isn’t in doubt or denied.
The argument is that it “isn’t ever switched on” and is a back up phone.
Ive called the phone twice and it’s rung both times. The owner denies this means it’s switched on. I’ve called it other times and it’s gone straight to voicemail (ie it’s clearly switched off).
If I send a message to WhatsApp and it has two ticks then it is definitely switched on isn’t it?