Steam Guard

Hello
i own a steam account with steam guard mobile but my phone was stolen (and of course, i did not write the code when activating the service).
i contacted steam support to prove my identity and that i'm the owner of the account but they don't care --'
i gave the email of creation (still unchanged), gave the ip's where i connected from (only 2 ip's), the phone number associated, the credit card associated with the account... But it seems that it's not enough. i don"t know what to do...

So the question is: is there a way to bypass or remove the mobile authentication or add a new phone (not the same number).
thanks for your help.

Where did you contact them? try phone calling.

And no, i don't think so; you're account is locked from inside.