I had a same issue and tried to use a external usb key board to escape this problem. However, I decided to replace the keyboard once I found the replacement keyboard from Aliexpress. Aliexpress seller sent me the keyboard approx 10 days. The biggest challenge to replace the keyboard of Bmax y13 is to remove the metal plates. If you take out screws and flat cables one by one, you will finally face the issue that the keyboard is covered by big metal plates. The metal plates are bonded by many plastic bits which can not remove easily. There are some other laptop is the same config, some website recommend me to use soldering iron to melt them to take metal plates. I started very small bits, then I understand how to do it gradually, Once you know how to, you will find this is not difficult tasks. After take off metal plates, we also need to get rid of keyboard back lights sheets, take off very carefully. Finally, we can replace the keyboard.
