I mentioned that I had already checked that it was enabled so unfortunately your solution did not help
Flash Player is a built-in component of Edge/IE. There is no separate installer.
Is the problem with Flash with one site, or all sites?
Here's my general IE11/Edge advice:
First, confirm that ActiveX Filtering is configured to allow Flash content:
You can try to work around these issues by using Compatibility View:
If that is too inconvenient, using Google Chrome may be a preferable alternative.