As you have taken the casino welcome bonus and received 100% of your deposit, there are certain requirements you need to meet before you can withdraw the money. The most important one is the rollover requirement; This relates to how many times you need to play. You can see your current status here in the 'Bonus status' section in "My Account" https://powerplay.com/casino-bonus/
Please, also see the full terms of this promotion at http://powerplay.com/promotions/ and click 'offer info' under the casino welcome bonus at the top of the page.
We can help you calculate how much more you need to play on our slots before you can withdraw. Please contact customer support for assistance.
Please note this is calculated for slots, other casino games require different rates. You can see more in the terms and conditions of the offer as per the above link.