Ubuntu 20.04 RICOH printer problem

I've just installed new Ubuntu 20.04 and started experiencing printing problems with my RICOH-SP-3225SNw, which I installed via network.

I am able to print the "Printer Test Page", but I for some reason I cannot print any PDF or JPEG files. While I press the Print button the printer does start moving but not printing, with no error messages neither in pooler, nor on the printer screen.

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