You will need to contact Green Dot Bank here:
Contact Green Dot Bank by calling (877) 233-8552
There are many reasons why your account may be permanently locked and you can review the Terms and Conditions here. Apple does not have your money and it is being held by the bank that must follow federal banking regulations that is beyond what Apple has any control over. It would be illegal for Apple to interfere with this process.
https://applecash.greendot.com/termsconditions/
If you feel the bank is not treating you fairly, you can file a complaint with the CFPB where many cases you will get a response within 15 days.
https://www.consumerfinance.gov/complaint/
Federal Regulations enacted by Congress including the Bank Secrecy Act and the Patriot Act require banks to follow procedures and investigate matters that they may not be able to disclose to you, otherwise those disclosures would violate the rules that congress has put in place.
https://www.fincen.gov/resources/statutes-regulations/guidance/unauthorized-disclosure-suspicious-activity-reports