I get frustrated editing with ArcGIS Pro when this happens to me - the trace tool either stops working or traces "ghost" features. I'll show you how to fix it.
M3 on the Esri Community and MichaelMedina802 in the comments below has a quicker workaround than shutting down the project - see his workaround here: https://community.esri.com/t5/arcgis-...
If you would like to buy me a dew, or sign up for an interview, here is a link for that: https://koji.to/@GIS.Chops