Q: I am a recent retiree, younger than 65, and have just received my final annuity computations. I expected Medicare would continue to be deducted and have now read two puzzling things: That Medicare is not taken from annuity payments, and that I must contact the Centers for Medicare & Medicaid Services to have payments withheld. By law, I understand Medicare becomes my primary payer, with my federal health plan second, when I turn 65. My question is: As a retiree under the Civil Service Retirement System, do I “owe” 1.75 percent of my monthly annuity to Medicare and must…