You can manage your available payment methods in your Preferences. To do this, select the menu icon in the top right corner of your screen and choose "Preferences". You can then use the on/off switches to enable or disable specific payment methods.
Disabling a payment method means you won't be able to use it for deposits or withdrawals. We always aim to process withdrawals back to the payment method you used for depositing. Therefore, if you're having trouble withdrawing, please check that the original deposit method hasn't been disabled in your Preferences.