Problem showing WebP with plugin

Hello,
First of all, thank you for your hard work.
I am creating WebP in plugin. I’m showing. I’m clearing the cache. Everything is very beautiful. When I checked, the memorized images are in WebP format. Perfect. But after a few hours or a day, the images I see as WebP continue as jpegs. I think it has an impact on the rankings and it’s important to me.
I know as WebP, but now I’m constantly checking from mobile. when i see jpeg i clear cache again. Then this thing repeats over and over. I want my entire site to be served as WebP.

Thanks.

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