clock and calendar quit when editing

the built in clock app crashes as soon as I try to edit an alarm or add a new one. Also, the calendar app quits as soon as I edit the start or end time of an entry. I have an iPhone XS max and I tried many things with no success. I

force restarted the phone, I have updated the IOS, I have uninstalled and installed again the calendar app. I deleted the défaut holidays calendar. I reset the default settings, changed the time, changed the region but nothing worked. This morning everything was working fine and now I cannot use these two apps whereas everything else is working correctly. I can even use the stop watch, the timer. Anyone can help?