Unable to replace older file version

This problem only started recently. I’m updating some previously recorded WAV files by exporting back to their home folders and overwriting the previous recordings. In exporting them, I discovered, the new versions were not replacing the previous versions. There was also no dialogue box asking to replace previous version. I don’t know if this is an OS X or an Audacity problem. Can someone answer the question?
I’m running OS X 14.6 and Audacity 2.4.2

Hi mikep. I don’t know much about macOS, but perhaps someone with more experience will pitch in here. I didn’t see anything like this in Google for Mojave 10.14.6. Something to try: Are you able to export successfully to a new file in the same directory?