One of the biggest tickets we get are from cancellations. I know its slow but if you mash the button a bunch during lag it seems to cause way more harm then good. If you have a balance error and don't want to wait for support. One little trick you might try is placing a very small order in the same coin pair for an amount that wont fill and cancelling it this forces an audit and may fix your issue. Try it on the buy and sell side might fix you right up. We have a fix for this but nothing is instant.
This worked for me. I had tried to place a order that didn't get posted, tried placing it again, still didn't get posted.
Came back an hour or so later to find that BTC for both trades had been deducted, leaving me with negative BTC, but neither order was posted.
Cancelling another order for the same pair fixed the issue, and restored my BTC balance to the correct value.
This only works if you have a positive balance of one coin or the other, or an open order that can be cancelled, without that you can't fix it yourself. Might be worth leaving a small amount of alt-coin sitting around, or a never-filled order, to allow this self-fix to work.