Mac OS Catalina can't record external mic

I am new to the forum and hope I have posted this in the correct location. I have a MacBook pro running Catalina 10.15.7 and Audacity 3.02 (I believe the latest version. Also am using a Behringher interface (Uphoria UMC 404HD) which connects to the USB on the mac. I have a condenser mic connected to the Behringer. Recording works fine if I set the Preferences to use the built-in inputs but when I change to the external mic connected to the Behringer, nothing gets to Audacity. I have set the security preference to allow Audacity and Garageband (which has the same problem), access to the mic. Also I can hear via the headphones connected to the Behringer the amplified signal coming from this mic. So this is beyond me, and any suggestions are greatly appreciated.

Let’s make sure that sound is getting into the Mac.

Click on Apple (menu) > System Preferences > Sound > Input. You should see the Behringer listed there (USB Audio CODEC). Select it then speak into the mic. Does the input level meter bounce?

– Bill

Thanks for the reply. Somehow late last night I did get Audacity to record using my external mic. Not sure how I did this. There are a couple of buttons on the Behringer I pushed (e.g. A/B Monitor and Line/Instrument input). Sorry I can’t be definitive but am not very experienced in this area,
Many thanks for your help.