It happens to me too. Also over $100 is gone. Mo email from IS is received about this yet. Let's hope it's just a glitch.

And surprise, surprise, istock has yet again messed something up that should be pretty straightforward. Part of my funds (less than $100) have been paid, part have vanished into thin air.

All of a sudden 112$ were deducted from my account, not all money gone only 112$!
Am I only one?

That presumably is the amount you earned from the last payout request on 21st January , to the end of the January. That money has been taken from your account ( and to be fair to IS all this information has been widely noted in FAQs on the site) and will be paid on the 25th February by whatever method you have told IS you want to be paid.
All your February money will accumulate until the end of February, and you will be paid all of Februarys money on 25th March, and so one, month on month.

 (beaten to the reply by someone else)

My money disappeared as well. No response to my message from iStock up to now. I am about to close my account...

Why would you need to close your account? All the information is widely available at IS about the payment situation, in FAQs , forum posts and emails to members. Given iS track record for past changes they seem to have handled this quite well.

You should have received an email today explaining what happened, apologizing for the delay, with a link to your Payouts Report that shows how much will be paid out on Feb. 25th. If you haven't updated your payout information yet, you need to do so by Feb. 10th in order to receive your payment on the 25th. Receive is a nice choice of words since depending on the payout method you choose, it will be a number of days before the money is in your hands.

Dear very very unhappy contributors, who can not read simple IS payment infos,
do not just talk and threat, how You will close Your accounts, but
 CLOSE  IT finally.

I hope they do close the accounts in waasted anger. It's more money for me.

You should have received an email today explaining what happened, apologizing for the delay, with a link to your Payouts Report that shows how much will be paid out on Feb. 25th. If you haven't updated your payout information yet, you need to do so by Feb. 10th in order to receive your payment on the 25th. Receive is a nice choice of words since depending on the payout method you choose, it will be a number of days before the money is in your hands.

I have just received the apology response first time from IS as you explained. Thank you for informing.