Chosen Solution
I have sunken keys in the middle of laptop keyboard due to poor installation by the service person and I have been refused further service. All the keys in middle of the keyboard and sunken, and it is due to having a lack of support under the keyboard., however it is still functional. If it is relevant , the keyboard model is HP Pavilion - 15-bc231tx
Remove the keyboard and see if the supporting base has been bent inward. Here’s how to do it: https://www.youtube.com/watch?v=BWZQ9opN… UPDATE This video should show you how to get to the battery: https://support.hp.com/us-en/document/c0…
Try unscrewing the back of the keyboard and if something is out of place, put it back to where it was. If some springs are broken, order replacements. If nothing is visible that is causing the problem, contact the manufacturer.