XPS 13 completely stuck

Hi! I had BIOS issues with my XPS 13 since I bought it, but I was somehow surviving in the hope that a new BIOS firmware would fix them. Today, however, my laptop froze and I had to apply a hard switch off. And now it does not work again. When I switch it on I get the DELL symbol on the screen but it just turns off after a few seconds. I tried plugging it but it does not help. Sometimes the led light blinks, with three yellows and three whites alternating endlessly. Does anyone know what to do?