URGENT: Audacity keeps changing kHz after exporting

Hi!! First time posting here, but I have an issue.
I have Mac OS X 10.13.3, and I’m trying to export an audio file as .wav, but it keeps changing the kHz from 44.1 to 48. My audio needs to be 44.1 kHz, and this is a very time sensitive question!!! If anyone can help me I’d greatly appreciated.

The sample rate for export is taken from the “Project Rate” in the lower left corner of the main Audacity window. Set that as required before exporting.

To set the default sample rate, go into Preferences and set it in the “Quality” section.
Note that importing files can override the default. See: http://manual.audacityteam.org/man/selection_toolbar.html#rate
and: http://manual.audacityteam.org/man/quality_preferences.html

It is highly recommended that you leave the default “sample format” as “32-bit float” (this does not influence the exported format).