Citibank Bank Account Or Service Complaint

Citibank Bank account or service department,

Other bank product/service Account opening, closing, or management California

In -/-/-, I have open a new checking account and deposit $15000.00 with city bank. I can get $400.00 Cash bonus if I keep the minimum balance of $15000.00 for the next 30 days that city bank said. But after 30 days they have't gave me the bonus. I went to city bank 3 times to ask my bonus back but they said that I have to wait the city bank main office send the bonus to my account. Today is -/-/-, I am still waiting ...