Welcome to the forum!
Is there any chance you have selected the original raster image by mistake? As you have probably learned, it often looks like nothing has happened when you do the trace. That's because the trace is on top of the original. Sometimes it can be tricky to select the new paths.
This is where the status bar is so helpful. The status bar always has something to say about whichever tool you're using and whatever you you're doing. So when you make the selection (with Selection tool) enabled, the status bar tells you what kind of object you have selected. If it says "Photo...." then you do not hae the path selected.
With the Trace Bitmap dialog, I always use the Node tool to select things. Then if I don't see nodes on something I selected, I know I have the wrong thing. (When the Node tool is enabled, the status bar says "Drag to select objects to edit". Not so helpful. That's why I look for nodes, instead of using the status bar, for the Node tool.)
There could really be a few different reasons for this problem. So if that wasn't the problem, we'll keep trying. It would be best if you could share the SVG file with us, so we could investigate directly (instead of playing 20 questions", you know). You could either attach the SVG file to your message, or upload it anywhere, and give us the link.
