Thanks for reaching out @lenarts1. When you mention it returns to original images, can you share more details and we’d be happy to assist. Are the images you’re uploading not resulting an a WebP or AVIF image being generated? If so, it’s possible that the images you’re uploading are already optimized, and switching to a WebP or AVIF wouldn’t result in any smaller size image.
It’s also possible that the browser or device you’re using doesn’t support the image format generated.
Please share more details of your experience and we can hopefully assist further. You can also share your Site Health information via this form if you’d like us to review your environment to see if we can spot anything unusual.