Was told by the trading platform support that my dividend was voided

I bought a stock on March 14th and the record date for that stock was March 17th and the ex-dividend date was set to one day ahead of the record date. Obviously I thought I was getting the dividend because I had bought the stock before ex-dividend date, plus there had been a pending dividend payment in my history section on Robinhood.

Earlier today, when I went on Robinhood to check, the pending dividend payment disappeared and it's nowhere to be found in the history section, so I contacted the support and they got back to me pretty fast and they told me I needed to purchase the shares at least three business days before the record date to receive the dividend payment, thus the pending payment was voided.

I only started investing in the stock market very recently so I'm not sure if that's a thing. From all the research I've done, I only need to own shares of a stock prior to the ex-dividend date to receive a dividend. Is that not the case?