[Grammar] Using "circumstances" to express the same meaning

[ucef]

Whatever happens, don't let anyone into the building without a proper identity.

....... should you let anyone into the building without proper identity.

I don't know how to use the word "circumstances" in the blank! Any clue?
Thank you.

 

[bureaucracy]

Under no circumstances should you let anyone into the building without proper identity.

/isn't a native speaker/

 

[MikeNewYork]

Whatever happens, don't let anyone into the building without a proper identity.

....... should you let anyone into the building without proper identity.

I don't know how to use the word "circumstances" in the blank! Any clue?
Thank you.

I agree with "under no circumstances" for the blank. I would change "without a proper identity/without proper identity" to "without proper identification".

 

[emsr2d2]

I agree with "under no circumstances" for the blank. I would change "without a proper identity/without proper identity" to "without proper identification".

... or "without proper ID".

 

[MikeNewYork]

... or "without proper ID".

Yes.