On May 12, Trump reached a 90-day trade-war truce with China, cutting the minimum China tariffs to just 30 percent. The higher rate was in effect barely a month, from April 10 through May 14. Businesses that had to pay the higher rate believe they were unfairly ensnared in Trump’s hasty negotiations. Attorneys say their clients have been lobbying the Trump administration and lawmakers for exemptions, including retroactive measures that would result in money back. Paying higher tariffs even once can have long-term consequences for small to midsize companies, attorneys say.