Check your quiz settings and make sure any time limit is set correctly. (The time limit specifies how long students have once they start the quiz, not how long it will be until the due date. For example I give students 3 day to take a quiz, but once they start there is a 10 minute time limit for each attempt.)
Also go to the assignment tab, click the three dot icon next to the quiz, select edit, and then in the pop-up select more options. On this settings page, check the availability dates. It is possible to adjust due dates using the calendar, but the availability dates do not change. That could cause the available until date to have been accidentally set too early for your due date.
Otherwise, I have not encountered this, and so it should be reported to canvas support
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