Where'd you get that Russia did it? There was an article going around some time ago that Ukraine special ops (or some sort of tactical strike team, not good with these military terms) did it. That does make sense, why would Russia destroy their own pipeline? They were still hoping Germany would change its mind under economic pressure. With it destroyed no chance of selling to Germans any time soon since it's now phisically impossible.
Edit: found it https://www.washingtonpost.com/national-security/2023/06/06/nord-stream-pipeline-explosion-ukraine-russia/ Edit2: my bad. different pipes