Certain keys not working on Apple Magic Keyboard with brand new MacBook Air

I have cleaned many times with a spray duster. I have checked the settings. I have done everything I can see suggested but have no clue why 7-8-9 stopped working. Please advise. I hate to buy another keyboard and have the same problem. This is just a regular typewriter keyboard without a number pad on the right side. It has worked fine for years and nothing has spilled or falled on these 3 keys so it is a complete mystery. Been going on for months now so restarting is not the answer. I hate to waste another $100 for a new keyboard after spending over a $1000 on a brand new macbook air which is much larger and heavier than my old model from 2017. So disappointed about that too. Thank you!

[Re-Titled by Moderator]