Set the Instant to “Saute” and allow to warm.  Season roast generously with salt and pepper. When Instant Pot says "Hot," add in olive oil and sear roast until browned on all sides. Remove to a clean plate.  Add in onions and carrots and cook for an additional 3-4 minutes, stirring occasionally. Deglaze with red wine, scraping the bottom of the pot to get all of the delicious bits. Add in the beef stock, rosemary, thyme and the beef.  Lock the lid into place, place vent to sealing, push "Manual," and set time to 1 hour 20 minutes. The Instant Pot will release some steam as it comes up to pressure, then it will seal automatically.  When the cooking time is done, allow the Instant Pot to naturally vent for at least 10 minutes, 20 is better. Using a wooden spoon, carefully push the valve open to release the rest of the pressure. Remove lid.  Skim a much fat off the top of the liquid as you can before disturbing the roast. Remove the roast to a cutting board and with two forks shred roast. Serve alongside carrots and onions, topped with the pan juices. Serve with mashed potatoes.