Blocked phone after 4 years of usage

I've been using the phone for 4 years. But after I've reset the settings - it got blocked. Not just blocked but it is stating that I've stole it from some company called "tech data"(cs.blocked@techdata.com).

I've bought it as a brand new from a local reseller.

Apple support states that it can do nothing about it without the "proof of ownership" which I don't store for such a long period of time.

What do I do with this phone(is this a garbage now)? Do I have a guarantee that any other device that I own will not be blocked in the future with the same reason? Why don't apple ask "proof of ownership" from that 3rd party company? Why wasn't it blocked when I just registered it, so that I could go to that local reseller?

Also if the phone states that I am a thief, why don't Apple with this 3rd party company go to police to retrieve this stolen phone and put me to jail?!