What " refresh " has happened @Blabancz
Is it the Samsung One Ui / Pie update ?
Also please ensure you have your particular Calendar still chosen in your settings.
Some Calendars are having issues showing the info due to them not being compatible with the users chosen theme after the Samsung One Ui / Pie update.
The options are to choose another theme or use Samsungs Stock Theme.
You can let the Theme Developer know the issue usually via their feedback option.
Daily Driver > Samsung Galaxy s²² Ultra 256Gb in Phantom Black.
The advice I offer is my own and does not represent Samsung’s position.
I'm here to help. " This is the way. "