bulk optimization to webep not working in free version

Whenever I try to start the bulk optimization to .webp file format for all files, I get the pop-up explaining that converting to webp AND avif is only possible in the registered version.

I don’t have this issue in other wordpress installations. Individually optimizing images does work.

I unchecked every possible avif option in the setting (like converting webp to avif).

Please help

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