Sadly, Asurion is what all the other carriers use for Insurance.
They went out and bought just about every other insurance company out there, a few years back. Everyone is on Asurion.
I can guess that the root of your problem might be because you reported it stolen.
If you reported it stolen, they require a police report. At that point, most people say it was lost.
next time use their website, phoneclaim.com
Got to understand, the reason its so difficult to make a claim sometimes is because of all the people that have abused insurance in the past (and still are). After all, they are a business.