Citibank Bank Account Or Service Complaint

Citibank Bank account or service department,

Other bank product/service Account opening, closing, or management New Mexico

I am retired and wanted to start collecting my pension last year from CITI. Based on the information they provided, I selected a monthly payment of $ -/month, which they started to pay. THEN, I received a letter dated -/-/2017 in which they stated they made a mistake and the monthly benefit would be only $96.00. I would NEVER have picked that option had they provided the correct information-I would have picked the lump sum option. At $ -/month I am unlikely to live long enough to collect the money in that account. To me, this is a case of FRAUD-telling somebody one thing and then changing it a few months later. In addition, they said they will charge me INTEREST on the overpayment!! How can they charge me interest for THEIR mistake? I contacted their office yesterday at ( - ) - and explained my situation. Somebody was supposed to check into it and call back, but I never got a call back. At this point, I would like to receive the LUMP SUM option for the money remaining in the account and NOT be charged interest for their mistake. This is looking like FRAUD to me. Thank you very much for anything you can do to help.