Coinomi support team helped me today with supporting links which i forwarded to Changelly. Subsequently, Changelly re-sent to me exchanged coins successfully on the same day. Problem was in low transaction fee used by Changelly due to which transaction has been stucked for a more than a month. It is important to mention that in such a cases transaction pending status has to expire before they could resend coins.
This doesn't sound like a logical explanation... If changelly used a low transaction fee that it's their problem. They should send a second transaction to the exchange that they are using to first get your transaction done. Or, they should have at least refunded you after 2 days of waiting.
The only reason people would use changelly instead of shapeshift is because their rates are better.
But does it really matter when you're waiting for a month? Similarly, why would anyone use changelly when you can use an exchange much quicker and for better rates as well?
Even though they've resolved this issue, they've taken far too long. Based on this experience i would not recommend changelly to anyone nor use it myself in the future.