FSA after retirement?

Hello:

 

I retired from the Federal Government in 2019 and receive an annuity.   I currently work for a private  employer that offers an FSA.  Can I take advantage of the FSA?  I have searched for the answer and find statements like "IRS code does not allow retiree/annuitants to utilize an FSA", but does that just mean you can't pay into an FSA with non earned income?

 

Thanks!