What should be done after data is stolen?

[ARandomPerson]

For the past 3 weeks, unknown individuals from various parts of the world have been accessing my Spotify, Microsoft, Steam, Instagram, and even Genshin Impact accounts without my permission, and I haven't been able to stop it. In the last 24 hours alone, there have been over 10 unauthorized logins to my Microsoft account, all from different countries, as you would expect. Today, I noticed that around 160 lira has been deducted from my bank account without any prior authorization or notification. I conducted a thorough antivirus scan on my computer, but it did not yield any results. Has anyone else experienced something similar before? What steps should I take to resolve this issue and prevent it from happening again?