Laptop does not start anymore. What now?

Hey everyone My laptop ran flawlessly for ages, but now it won't start… As soon as the laptop is plugged in, the lamp for the battery lights up red. When I switch on the laptop… It beeps once very briefly and gives a humming sound for 2 seconds, as if it were starting. The humming stops immediately. (To introduce: how a car / moped does not start) The laptop stays black. What should I do?

With mine it always works to disconnect the laptop from the power (i.e. Pull out the charging cable and remove the battery), then wait briefly and then plug the battery / charging cable back in and switch it on.