Gang bank account not working?

[4rjan]

• /gbank (amount)
  Use this command to bank your money in the gang bank.
  See also: /gbalance, /gwithdraw
  
  
  
• /gbalance
  Use this command to check your gangs bank balance.
  See also: /gbank, /gwithdraw
  
  
  
• /gwithdraw (amount)
  Use this command to withdraw money of your bank account.
  See also: /gbank, /gbalance
  

These commands do not work? do i need to open an account or something?