Our observed flows added through a CSV file match the content in the Data section, however, in the results view when looking at streamgauge comparison, they fluctuate eg. 119 is now 124.9 for the same day and month. What could be happening?

If you are looking at the streamflow gauge comparison result, you should see observed and modeled clearly labeled. It sounds like you are in this screen, the observed flow should match that in the data tree. So the main thing I could think of would be to be sure that the units are the same in results. Does this help, or are you still finding different results?

Note that in the "streamflow" result, the observed flows are shown for the stream reach for the streamflow gauge object, but the adjacent node streamflows will all be modeled flows.