I am 10 months older than my wife. Her SS benefits are larger than mine, so I filed for retirement at full retirement age, and she began receiving spousal benefits. Last November at the age of 70 when she filed for benefits on her own account, I planned to change to spousal benefits on her account. But we were told by the SS representative that I could not. My increase would have been over $100/month. Is what the SS rep told me correct? Thank you.
You couldn't change from drawing your retirement benefits to drawing just spousal benefits, but you could file for an additional spousal benefit if you're eligible. To be eligible for an additional spousal benefit, your wife's full retirement age rate, or primary insurance amount (PIA), would have to be more than twice as much as your PIA.
If you think that you should be eligible for spousal benefits you can re-contact Social Security and insist on filing an application. Note, however, that your spousal rate (if any) would be based on 50% of your wife's PIA, not 50% of her age 70 benefit rate. And, if your own PIA is higher than 50% of your wife's PIA, you won't qualify for spousal benefits.