LONDON—British online fashion retailer Boohoo warned on Thursday that full year profit margins will be lower than its previous guidance due to a rise in freight costs in its supply chain and higher wages for its distribution centre workers. Shares in the group dropped 11 percent, extending year-on-year losses to 37 percent after it said full year 2021–22 adjusted Earnings Before Interest, Taxes, Depreciation, and Amortization (EBITDA) margins were now expected to be 9 percent to 9.5 percent, compared to 9.5 percent to 10 percent previously guided. “Elevated short-term cost headwinds experienced in the first half are expected to continue in H2 alongside recent freight inflation in our supply chain and wage inflation within our distribution centres,” it said. The group, which is seeking to improve its image after negative publicity over supply chain failings, also raised its guidance for full year capital expenditure to £275 million ($376.2 million) from …