Only new uuploaded images are showing as .webp

optimized the images on my website using the Optimize Images & Convert WebP plugin, performed bulk optimization, and as far as I understand, it should have converted the images to .webp format. However, while in the library, the old images are shown as ‘optimized’ and ‘converted to .webp,’ but these images still open as .jpg or .png. New images, on the other hand, open immediately in .webp format.

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