IF the contract was already accepted, it cannot be subsequently refused or declined for this reason: a contract, once accepted, is binding. However, if it was not accepted, then it could be refused for this or essentially any reason: the law gives residential real estate sellers enormous discretion in terms of what offers to accept (or not), and they can decline offers for any reason at all, even silly or stupid or factually unsupported ones.The only exception to the above: they can't discriminate against you due to your race, religion, national origin, sex, or disability. If you believe the refusal was really for one of these reasons, contact HUD about possibly filing a housing discrimination complaint.