If you want to withdraw all the balances in the coinbase account and never want to use their service means you can request for account cancellation here :
https://www.coinbase.com/settings/cancel by doing this you can withdraw the balance on your suspended account.
Did you violated any of their terms in the recent days?
Possible reasons for suspension and termination could be found here
7.1 Suspension, Termination and Cancellation. We may: (a) refuse to complete, or block, cancel or reverse a transaction you have authorised (even after funds have been debited from your Coinbase Account), (b) suspend, restrict, or terminate your access to any or all of the Coinbase Services, and/or (c) deactivate or cancel your Coinbase Account with immediate effect for any reason, including but not limited to where:
we reasonably believe that we need to do so in order to protect our reputation;
we are, in our reasonable opinion, required to do so by applicable law, regulation or any court or other authority to which we are subject in any jurisdiction;
we reasonably suspect you of acting in breach of this Agreement;
we reasonably suspect you have breached our ‘Behaviour Policy’ or our ‘Policy on Prohibited Use, Prohibited Businesses and Conditional Use’ (as set out in Appendix 1);
we have concerns that a transaction is erroneous or about the security of your Coinbase Account or we suspect the Coinbase Services are being used in a fraudulent or unauthorised manner;
we suspect money laundering, terrorist financing, fraud, or any other financial crime;
use of your Coinbase Account is subject to any pending litigation, investigation, or government proceeding and / or we perceive a heightened risk of legal or regulatory non-compliance associated with your Coinbase Account activity; and / or
you take any action that may circumvent our controls such as opening multiple Coinbase Accounts or abusing promotions which we may offer from time to time.
We may also refuse to complete or block, cancel or reverse a transaction you have authorised where there is insufficient E-Money in your E-Money Wallet and / or insufficient Digital Currency in your Digital Currency Wallet to cover the transaction and (where applicable) associated fees at the time that we receive notification of the transaction or if your credit or debit card or any other valid payment method linked to your Coinbase Account or Digital Currency Wallet is declined.
7.2 If we refuse to complete a transaction and / or suspend, restrict or close your Coinbase Account, and / or terminate your use of Coinbase Services, we will (unless it would be unlawful for us to do so) provide you with notice of our actions and the reasons for refusal, suspension or closure, and where appropriate, with the procedure for correcting any factual errors that led to the refusal, suspension or closure. In the event that we refuse to complete a transaction and / or suspend your Coinbase Account we will lift the suspension or complete the transaction as soon as reasonably practicable once the reasons for refusal and / or suspension no longer exist. However, we are under no obligation to allow you to reinstate a transaction at the same price or on the same terms as the suspended, reversed or cancelled transaction.
We may suspend, restrict, or terminate your access to any or all of the Coinbase Services and/or deactivate or cancel your Coinbase Account, without reason by giving you two months’ notice. You acknowledge that our decision to take certain actions, including limiting access to, suspending, or closing your Coinbase Account, may be based on confidential criteria that are essential for the purposes of our risk management and security protocols. You agree that we are under no obligation to disclose the details of its risk management and security procedures to you.
source :
https://www.coinbase.com/legal/user_agreement 
