The ruling, issued last week, is unrelated to a different judge’s ruling last week that the city and School District must repay nearly $50 million in 2018 taxes to owners of about 700 commercial properties. But it delivers another blow to the Office of Property Assessment, which has faced criticism from property owners and City Council members in the last year — especially for its 2019 and 2020 reassessments that increased tax bills for hundreds of thousands of homeowners.