That is because they are applying the miner fees, but the fees from changelly are less than 0.25% if i am not wrong (nothing)
I have already said it, there is no way to avoid fees.
So I'm totally new to this, I researched on some currencies and thought to myself that I should invest while they're at such a low price. I buy like 200$ worth of bitcoins. I pay 20$ worth of fees for the exchange (changelly).
If you do not want to spend a lot of money in exchanges, just put your money on an exchange, it is not a safe practice, but you are not going to pay money for fees, well, just the fees from the platform.
Maybe you are just going to risk your safety for a few bucks, but if you are looking for that.. just do it.