I just cannot not leave a positive review.

[Marika33]

Can we say "cannot/can't not do something" in English?

• I just cannot not leave a positive review.
• I can't not call him now and ask him about everything.

 

[Piscean]

Yes, but can't is far more common that cannot.

 

[Tarheel]

It's a way to say you feel compelled to do something. It's not that unusual either. The feeling won't stop bugging you until you do it (whatever it is).