Amazon suffered glitches in the opening minutes of Prime Day on Monday, displaying errors on the e-retailer's main site.

Amazon's annual shopping holiday kicked off at 3 pm E.T. and runs for 36 hours, the longest Prime Day yet. Shoppers reported several errors — on both the desktop site and the mobile app.

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Some saw an error page featuring the "dogs of Amazon." Some got caught in a loop of pages urging them to "Shop all deals." Clicking the entry link for a specific category returned the user to the first page urging them to "Shop all deals."

Amazon did not immediately respond to requests for comment from CNBC.

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