Audio sound is different after exporting

I have a problem that appears after applying noise reduction in audacity. The audio is completely different from that edited in audacity and noisy.
So is there a way that makes the edited audio nearly the same after exporting In .wav? Because it takes so long to export and then re-listen to the audio and if it is not satisfying, I will repeat the whole process from the beginning.

Yes. There was a problem with Noise Reduction in the 3.4.0 and 3.4.1 releases. The difficulty should be resolved when 3.4.2 is released.

In the meantime, re-install 3.3.3: Old Audacity versions download

I found out that I am using version. I still have a problem that sound is different in audacity and after exporting In .wav. How to solve it.? I have to export and listen and then edit again . It’s exhausing.

I don’t know. Perhaps someone else has an idea.