For some reason the IRS has that you have one in their system. Did you have insurance through the marketplace? Even if it was as a dependent on another persons policy? If so, you will need to contact the marketplace or the person who's policy you were covered under and enter that on your return.
If you did not have any coverage at all through the Marketplace, you will need to contact the Marketplace (by phone to talk to a live person) to find out why they are reporting that you do have one.
If you absolutely do not have one, then you can try entering $1 in for January column A to see if that will allow you to submit your return. Enter all 0's for the marketplace identifier and the policy number. Do not enter anything else in the columns. This may allow your return to be accepted. If it is still rejected, you will need to print and mail you return.
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