For security reasons, when you change certain settings on your account, it automatically freezes withdrawals for a number of hours depending on the setting that you have changed.
The key changes that cause frozen withdrawals are:
Change of password (72 hours)
Modifying address whitelisting settings (48 hours)
If you have not changed any of these settings above, please contact support via the chat box on the bottom right corner and let us know your email address, or just email us at firstname.lastname@example.org
If you have a KYC-verified account, this restriction can be lifted. Just email us at email@example.com from the email address you used to register with us for further instructions.