The wagering requirement is the playthrough amount that is required in order to qualify for a withdrawal of winnings.
An example of a $20 no deposit bonus with a 30x playthrough in simple mathematical terms is 20 x 30 = $600. Whereby the player must wager $600 before qualifying for a withdrawal on winnings. You can contact support or live chat to check the wagering you have completed as you play your bonus, this will give you a good indication if you are close to a win or not.
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