Audacity too slow and big after not closing it during editing

I recorded an audio file that was over 50 minutes long and I was editing it until a certain point when the program became extremely slow.
I ended up forgetting to close and reopen Audacity during editing (a tip I read in other topics).
I noticed that even after removing the parts that didn’t sound good, the file kept getting bigger (I used the OpenVino and DeClicker filters - at 8 minutes it’s over 1 GB, with a maximum peak of -12 dB).
I’ve tried creating a new file (Ctrl + N) and pasting the audio, but it’s still slow to edit. Even with just a few seconds of audio from that file it’s slow.
With other and new files the speed is normal.

I’m using version 3.7.1 specifically to use OpenVino.
Could anyone tell me if it’s possible and what I could do to “save” the file and be able to edit it at normal speed?

I would think that pasting the data from one copy of Audacity to another would just copy the problem along with it.

Try exporting the audio to a WAV file, then restart your computer and import that file to see if the problem goes away.

That problem goes away, but the WAV file has a noise that it’s not in the “original” .aup3 file. Three times applying Noise Reduction and this didn’t remove it such as it is in the .aup3.
Thank you for your attention.
I will consider the experience as a cost for education (Edit and close Audacity more times)