Senior Citizens (65+) With Financial Regrets From Their 20’s

I am looking for senior citizens ages 65 and older who can comment on financial regrets that they have from their 20’s. What did you wish you knew about finances that you know now? Looking back, what is your biggest regret? What advice would you give millennials about their finances that you wish you had at your age? Are millennials better suited financially than you were at that age? What smart financial decisions are millennials making? Requirements: Fit the age requirements of 65 or older, but open to minor leeway on this. Current finance professionals preferred but not required.