some keyboard stopped working

Dear all,                                                             

These (MJU7NHY6) keys in my laptop dell (Inspiron 11-3000 series) keyboard stopped working this May 13. They wouldn’t function unless pressed so hard. I bought laptop last year and it's new.

The onscreen keyboard is working fine. I updated the keyboards driver but it didn’t help. I’m not aware of any liquid that may have spilled over the keyboard. Maintenance shops where I'm seem they can’t help. Some said would give it a try and remove the keyboard to see if they can identify and solve the problem but said that there’s a chance it may screw up the whole keyboard. Please advise what to do. Enclosed is a snapshot of the keys in questions.

I appreciate your advice.

here's a snapshot of the keys in question: 

Best,