Uly, can you check if the sentences below are grammatically correct?

I am sorry for the bad experience you had at my shop, It is very unusual that one of my technicians would not have known if your vehicle requires synthetic oil. You may have been spoken with a gas cashier who has limited automotive knowledge. We would have corrected the problem immediately had I or my manager been aware of it.

in the fridge

I am sorry for the bad experience you had at my shop. It is very unusual that one of my technicians NOT KNOW if your vehicle requires synthetic oil. You may have _ spoken with a gas cashier, who has limited automotive knowledge. We would have corrected the problem immediately, had I or my manager been MADE aware of it.

Great, thanks!
One more thing. Would the meaning be different if we say: You MIGHT have spoken with a gas cashier, who has limited automotive knowledge.
In other words, what would be the difference if we use MIGHT instead of MAY

no difference

And that's the confusing part for me. I've learned that if there are two words/versions then there should be some difference. Are you sure it doesn't change anything? there must be something...

In some context, it does change things, but not in this one.

would you come up with an example where it does change the meaning?

For instance, “you may/might have spoken to Russ” is a suspicion that this is what happened; “you might have spoken to Russ” can be another way of saying “maybe you should’ve talked to Russ (and not someone else)”

So, you're saying that in your second example the sentence “you might have spoken to Russ” equals to this sentence "you should have spoken to Russ"?

Yes. Sometimes we use MIGHT for gentle suggestions: “If that key doesn’t work, you might try the other one.” You can’t use MAY like this.

Hmm, why can't we use MAY here? I think we can: “If that key doesn’t work, you may wanna try the other one.”
Sounds good, right?

MAY WANT TO isn’t the same as just MAY))

still, it looks like often we can use MAY and MIGHT interchangeably. is that right?

A lot of the time, but not always.

finally understood, thanks. the torture is over )))

👍🏼😉