When i use right keyboard j and i then i can't use the left keyboard s

[1481473819]

The problem just appeared now，there was no such issue before
when i hold j i keyboards, Pressing the S key on the keyboard is useless

[ZEgroselia]

As far as i know this is a keyboard thing, there is a fixed post here that talks about something like this, basically you need to change the keybind in certain types of keyboard because they can't register if you press some combinations of keys at the same type.

[loko loko]

Your keyboard most likely lacks of n-key rollover, which is a hardware limitation of your particaular one. The game itself has no issues picking up any standard keys and combinations. The keyboard you're using simply can't process some obscure combinations due to its matrix design. The only way to overcome this problem is to use another keyboard. My PS/2 keyboard could handle only 6 keys at once and even that was a very small selection of the keys due to how the keyboard was divided into several sections.

[1481473819]

Indeed, I replaced my laptop and then this problem occurred. According to what you said, these three buttons really can't be pressed together