YEs They have gone scam or had a major business problem at the very least.
They have my .2 ether now for over a week with no human reply to any of my tickets.
I had used them almost 7 8 times and no problem and now failed transaction for over a week with no reply to my tickets. I am steamed
that they would abuse my trust and have such horrible customer service like this.

Changelly reply to your tickets and return people funds ASAP or face the wrath of the community.
We will sue the pants off of you and work with the police to find you.

That being said I think they were at one time an honest company and they seem to have fixed similar problems in the past albeit taking weeks.