They are maybe overloaded with support tickets, it's a trend on crypto exchanges. kraken receive 10,000 tickets daily. Cryptopia is becoming more and more popular recently. Look in the "service" section in this forum, there is topic about Cryptopia where they are somewhat active to reply, maybe you should try there as well
Ok but you Cryptopia are an exchange that ask 5 BTC to list any new coin, and you have hundreds already listed (make your maths), you earn tons of BTC daily from trades fee....FFS you can't afford to pay a bunch of skilled guys, build a decent customer support and offer a great level service?
Exchanges ask for enormous fee without offering a counterpart service neither far the worth of amount paid!
Such a shame.