a universal backpack chest strap can help. it is a cheap solution but comes handy. https://www.amazon.com/Amlrt-Backpack-Chest-Strap-Nylon/dp/B07Z86C1NR

I was lugging around 25 lbs [2 laptops, chargers, rain jacket, protein bars, paper etc] in my journeyman backpack last week around airport on a work trip. I was wearing a leather jacket and the slippage was even worse. I am looking to get one of those chest straps for my next trip.