Where do I report a suspisous account?

I recently got matched with a play who had a very interesting op.gg. He has been bronze/silver for 3 season and then immediatly jumped to diamond in season 7. I did not know how or what to report this as and don't know if I even should but if someone could help me with this it would be nice.

We're testing a new feature that gives the option to view discussion comments in chronological order. Some testers have pointed out situations in which they feel a linear view could be helpful, so we'd like see how you guys make use of it.

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