Today (28. June 2023) an earthquake swarm took place in Krýsuvík-Trölladyngja volcano in Kleifarvatn lake. Largest earthquake had a magnitude of Mw3,2 at 09:21 UTC and was felt in Reykjavík area and other nearby towns.
Its unclear what is going on at this location. Most likely explanation for this activity is stress changes because of inflation in nearby Fagradalsfjall volcano. At the moment, I don’t think there is going to be an eruption in Krýsuvík-Trölladyngja volcano. This earthquake swarm looks like its ongoing at the writing of this article.