why my keyboard i can't press Y button but the other can. how to fix it?

What’s the model? Check Synapse settings, maybe it’s disabled/bound to some other function. You can create new (empty) profile or reset your keyboard to default settings via Synapse.

Hello JETDesertSandfresh804,

Were there any incidents that happened to your device before the issue? Is there any noticeable dust or dirt on your keyboard? Does the behavior happen while the Razer Synapse is closed or disabled? Please perform the troubleshooting steps from this article to resolve the problem. If you need additional assistance, PM me your device's serial number so I can verify its model. Have a good one!