as a seller on amazon ebay also aliexpress,i would like to answer this question.
there may some reasons for your order being closed without shipping out.
1.if you use a credit card ,west union or some delayed account(not instanly),the aliexpress will audit your record,which will take about at least 24hours to confrim your order,then the seller can ship out your ordre,some credit card with bad history record will be rejected,you will receive an email and get your money in several days;
2.if you choose a pretty low price product,much lower than their peers and the seller don't have any rating or selling feedback,you should be cautious.the seller may not ship out your parcel so don't waste your time on this seller(don't worry,aliexpress has some penalties for this kind of seller)
3.all orders has a shipping time,1-7 working days,if the product you ordered was out of stock,when the shipping time expires,your order will automatically closed,you will receive an email,and you will get all your money back in several day(depend on the type of card ,the arrival time will be different)
4another tips,if you want buy some affordable product with good quality,you can get it because china is the world factory,but if you want big brand like Nike or coach with a low price,it will be fake,hope it will help you guys