Board Thread:Questions and Answers/@comment-44024990-20191007202741/@comment-6697950-20191007203554

Because manga numbers don't correlate with LN numbers... A single volume of a manga can't possibly cover as much content as a text-heavy LN volume. A single LN volume takes 3-4 volumes to cover, so what you're reading isn't Progressive LN V6 content, but Progressive LN V2 content in Progressive manga V6.