Your letter is dated July 30 but you needed to enter Canada by July 28. How is that possible? What more does the letter state as above iIt says “This letter is important . because it contains information that will be used by the Canada Border Services Agency to issue your work permit .”
What is the job/NOC and LMIA that you have received? Have you paid money? Promised anything free - airfare, food, accommodations?
Job is Delivery driver and they offer food and accommodation free