Third party applications, like TweetCaster, cannot suspend your account, nor do we have access to Twitter users' account information.
If you are receiving a suspended message, you will need to contact Twitter Support to un-suspend your account.
You can do that here:
https://support.twitter.com/articles/15790-my-account-is-suspended
Hopefully they should be able to get you fixed up. Once Twitter un-suspend your account, you should be able to return to using TweetCaster as normal.
Twitter says my account is suspended?
