Which site is it? https://www.ssa.gov/ ? There may be particular online applications run by SSA that have not been updated in recent years, and due to changes in Firefox 57 that reduced support for older sites with nonstandard code (so-called "Quirks Mode" sites), the information you received might be correct. I guess you could see how far you get in Firefox. Or, since money and sensitive information are involved, perhaps it's better not to experiment, and just follow their recommendations. Assuming it was the real Social Security and not a scammer!