Just to clarify: "both have HSA's one is a self-only and the other is a family HSA."

HSA accounts are individually owned. There is no "family" HSA. There is the Right to have an HSA because of specific types of coverage. For instance, the person who owns the "family" HSA might go on Medicare before the other individual, so that HSA account is no longer qualified to receive contributions.

"the sum of the amounts on both form's line 3 exceed the maximum family amount of $7,100 for the year."

It seems they need a corrective distribution and there's still time to do it for 2020.