Calendar displaying day wrong

I'm implementing this library on my project and the days are displayed wrong for example: May 22 wich is Monday is being displayed as Sunday. Does someone know the cause of this issue?
![image](https://github.com/ApplikeySolutions/CosmoCalendar/assets/127444378/88795712-6713-4e64-80dc-d7c7b9b8460e)

Sorry for the broken english, not my native language.