Is the payback of an Obamacare subsidy deductible for 2018 as health insurance if paid back in 2019? If not, how about in 2019?

My wife qualified for Obamacare for the first 3 months of 2018. After the first quarter the cost was out of reach so she was uninsured. Then as our income improved we now must pay back the subsidy for the first quarter.