PlentyOfFish has reported that it suffered a data breach recently

https://www.ibtimes.sg/this-popular-dating-app-suffered-serious-data-breach-you-should-update-it-now-36552
https://www.techradar.com/news/plenty-of-fish-leaks-private-user-information

A new eHarmony database hacking incident?
https://onlinedatingsoundbarrier.blogspot.com/2019/11/a-new-eharmony-database-hacking-incident.html

Brazilian PlentyOfFish (POF) profiles on sale (via hacking incident perhaps)
https://onlinedatingsoundbarrier.blogspot.com/2018/11/brazilian-plentyoffish-pof-profiles-on.html

POF technical issue that was a hacking incident?
https://onlinedatingsoundbarrier.blogspot.com/2018/10/pof-technical-issue-that-was-hacking.html

A Match "glitch" reactivated a bunch of old profiles, raising concerns about user data
https://onlinedatingsoundbarrier.blogspot.com/2018/04/a-match-glitch-reactivated-bunch-of-old.html