Calendar in web app is blank/no activities showing in the calendar?

Hi. I have not used my Fenix 5x for several years. I recharged it - and did a lot of activities yesterday. My calendar is blank - but the activities shows up in "activities". Any solutions, anyone? I will attach som screengrabs (in Norwegian, unfortunately). Thanx a lot, everybody. Hope to hear from you. Best Mads Shows up in activities