Laptop keyboard presses enter+"L" when I press "L" key and "-." when I press the "." key-.

[coal760]

I have tried everything I could find online about this problem:

The on-screen keyboard seems to work fine (so the characters seem to be mapped to right place).
This is on a brand new keyboard, and now both this and the old one have had this same problem (the first was the one the laptop came with)

This is on the Dell Inspiron 15-7559. I replaced the old keyboard because keys were falling off and this problem started when I spilled a drink on it. Sticky keys are definitely off.

Is this a fixable problem? I dried the inside out carefully twice times to make sure, but that seems not to have worked.

 

[hang-the-9]

Issue started after a spill, which means it's likely an issue on the motherboard since issue is there on a new keyboard.