WebP Express blocks image uploads when uploading from the WordPress App for iOS

I am currently using webP express on a private LEMP server, with a WordPress installation on it. When I activate and configure the plugin, along with configuring Nginx, the plugin seems to work fine when uploading from my computer directly to the web browser.

However, I am also signed into my WordPress admin page from the WordPress app for iOS. In this case, when using the iOS app to upload pictures while WebP Express is activated, the uploads consistently fail with the message “Failed to insert media. Tap for more info.” If I tap for more info, a pop up appears and it reads “Media Options The request timed out.” When I deactivate the WebP-Express plugin, and then try the iOS upload again, then the upload works perfectly. So it appears that there is something in the plugin that is somehow blocking or causing my iOS WordPress App uploads to time out. I have no idea how to start debugging this, and could really use some help getting the plugin to allow uploads from the iOS WordPress app.

Can someone please please reply and clue me in on how I can fix this, or at the very least, start debugging it?

Thanks!

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