BOKU 5030

I suddenly got a message from BOKU5030 that this month I already spent 53,97 euros (May 29, 2023) ! I do not remember doing business with this service and am very suspicious what kind of a firm this is. How come this firm can charge me with this amount and why is there no specification, warning or other means of identifying themselves.

How can I get my money back, since I did not give permission to this firm to distract any money from any account of mine!