How do I record additional self-employed health insurance premiums not on 1095-A? (I did buy on the exchange, but paid for son's insurance through college plan).

It appears that in Forms, Line 17 of 1040 Schedule 1 is locked (because of the 1095-A entries, I presume), but if I try to remove 1095-A, I am warned the IRS will reject my filing without including it). I should be able to deduct his premiums, as well as the premiums on the exchange for the rest of my family, as I'm self-employed and have no other insurance options.