Click the limits box labled 1
Set limits of x and y axis appropriately in box with arrow labeled 2. Those are my settings to achieve that window.
Also note, the circled box in the bottom right will set the x-axis to 20hz-20,000hz instantly or 10hz to 200hz.
Second of all, your measurements in general seem way too low. I know the y-axis is semi-arbitrary values, but yours seem really low, especially your midrange from 100hz to 2khz.....Like noise floor low. There is some play in those values and you can simply just change the microphone volume in windows to impact them, but yours seem even low compared to doing that. I would expect to be at least above 60db to have that issue.... At least on any computer I have used, the measurements were still at a minimum above that.
This could be a multitude of different things, wrong setting in REW, wrong setting in windows/mac, wrong gain structure on dsp/amps, too low of HU volume, etc. SO unfortunately, unless you can guarantee that is just do to a simple setting and it doesn't really matter it is hard to tune.
If you measure with nothing on that should be your noise floor, it can also be seen in measurements as the blue circled below. In this example I was about 35db above my noise floor when Measuring.
These are also the settings in my RTA window. I use Pink Periodic (PN) Noise at 64k generated by REW. These settings will only apply if you are using similar periodic pink noise that is 64k.