Getting Flash Player "Error" after publishing

Hi,

I m trying to publish my website from Animate CC and I m getting following "error" on the web site : Download-Button for the Flash-Player, although it is the up-to-date version. The swf-file in the html-page consists of two into the timeline integrated flv-fildes. With the stand-alone flash player the swf-file is fully working.

Any idea what´s wrong? I would be greatful for each help.