Once you deposit funds into your PlayUp account, you will only be able to withdraw those funds once they have been turned over (I.e. once the funds have been used to bet on any fixture at odds greater the $1.01)
This means your account balance and the amount you can withdraw from your account (Withdrawable Balance) may be different.
For example if you have a total balance of $400, but $200 of that is a deposit and the other $200 is winnings from a bet, you'd have withdrawable balance of $200. The remaining $200 deposit would need to be turned over to be withdrawn.
Your "Withdrawable Balance" can be found in the "Account" menu under "Withdraw"