my mom is holding a multiple visa and got 45days left before it expires., got advised from a canadian immigration officer to get a new or renew her visa so we decided to let her travel here in canada for my husband is in medical condition and we need a family member to take care of our children and renew or get her a new visa when she arrives here but unfortunately when she was in the airport upon checking in she is told that her visa is already VOIDED. We didnt get any notice or advice that the visa is no longer valid even my mom is not aware they should atleast marked her visa attached so she knew that this is no longer valid. What should we do.