The Family Size is two.  That is the number of people on the tax return.  In most cases, that INCREASES the credit and/or REDUCES the repayment.

That has nothing to do with the repayment limit.  The repayment limit is based on Filing Status.  If the taxpayer is filing as "Single", the limit is $1500.  If it is anything else (for example, Head of Household), the limit is $3000.