It sounds like you have the Windows 10 Creators Update installed. To verify go to Settings > System > About. If Version is 1703 and OS Build is 15063.96 you have the Creators Update. In this update Microsoft changed the default behaviour of Flash as it moves to preferring HTML5 over Flash in Edge, and setting Flash as click-to-play by default.
Please do the following:
- Look on the address field. Is there a puzzle piece?

- If so, click that to display the 'Adobe Flash content was blocked message,with the option to 'allow once' or 'always allow' for this site

If the puzzle piece is not visible in the address field, do the following:
- Look for the 'Download Flash' link or the 'Get Adobe Flash Player' button on the page
- Click on the link or button
- The 'Adobe Flash content was blocked' message will display

- Click either 'Allow once' or 'Always Allow'
Note that this new behaviour is per-site, so you will need to do this for other sites that use Flash. Microsoft does not offer an 'always allow, for all sites' option. For more information, see Extending User Control of Flash with Click-to-Run - Microsoft Edge Dev BlogMicrosoft Edge Dev Blo
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