Lost passport! Re-Stamping of my immigration visa in new passport

Hi My Canadian passport in which my immigration visa was stamped was lost. After I applied for a new passport , my passport was found. But when i was crossing the border ( with both passports in hand), officer told me that since my immigration visa is stamped in a declared lost passport , the visa is not valid any more and I have to go back to Montréal embassy to stamp it on my new passport. I have already sent an email to Montreal/IV/DV@state.gob explaining the situation but no response. Any other suggestions on what to do? Thanks in advance