My Social Security Income only increased by $660.00 last year; however my taxes due on SSI increased by $500.00???

I had a deduction from my IRA which was required after I reached 75.  Box 7 on my 1099-R says IRA/SEP/Simple.  Last year I received all of that money, but this year I have to pay $514.00. What happened?  As I stated above, I only increased income by $660.00