It’s always best to clean a keyboard with a microfiber cloth and spray a solution onto the microfiber cloth and not directly on the keyboard. It’s best to use a cleaning product made for electronic components to clean your devices. There is not too much context in your question, so could it possibly be that you sprayed the keyboard directly with the cleaning solution? If so this could possibly be the problem. It’s possible you’ve cleaned the keyboard the same way before, but eventually this could cause liquid damage.