2-Channel Turntable Recording Issue: both on one channel!

I am still fairly new to mixing and recording audio, so I will try to explain my issue to the best of my abilities. My setup consists of my turntable which connected to a Mixer, an input going to my Behringer UFO-202 preamp (preamp set to line) which then connects to my laptop via USB, and an output going to my receiver. I am running Audacity version 2.2.2 through Windows 10.

After recording an album of mine and going over the audio, I noticed the audio was not recorded with their respective left and right channels. Instead, the channels were essentially recorded onto one channel. Keep in mind that I am using stereo tracks when recording, and I checked the audio coming from the mixer, as well as my preamp with my headphones, and the dynamic left/right channels were there. So this leads me to believe that the issue is occurring somewhere during the recording process. I just cannot seem to put my finger on it!

I am just curious as to how to fix this issue because a lot of the dynamic audio in the songs I am recording is drowned out and hard to hear when all the audio is on a single channel. Hopefully I provided enough information and a solution can be found! Lastly, this is my first forum post! I am very excited to be a part of this community, and hopefully learn a thing or two while on here!

There’s a few things that could be causing the problem. To narrow it down, please try the following 2 tests and tell us what happens:

  1. Temporarily disconnect the left output from the turntable to the mixer and make a test recording.
    (reconnect it after testing)

  2. Temporarily disconnect the left output from the mixer to the UFO-202 and make a test recording.
    (reconnect it after testing)

Question: Why do you have the turntable going through a mixer before the UFO-202?