Cannot save at new Sample Rate

I am using Mac 12.0.1 and I tried the issue on Audacity 2.3, 3.0.0 and 3.1.3.

I have MP3 files at 44,100 sample rate and I resample them to 48,000 (all good so far). The new sample rate shows on the screen.
I then want to save the file as a new MP3 and it only saves at 44,100. I also tried to save as WAV. Same issue.

I tried to fully uninstall Audacity, try other versions but still the same issue.
I generated a report (see attached).

How can I solve this? (10.7 KB)

Change the project-rate to 48000Hz before saving as MP3/WAV.