Forced to use New Outlook wiped my entire calendar, can I get it back? Can the tray icon clock calendar be connected to New Outlook?

For years I used the tray icon clock to open a calendar. It looked like this (except Save & More Details were not greyed out).

Clicking a date I could fill out "Add an event or reminder", add a time and location.

Jan 10 2024 "New Outlook" auto imposed itself. It insisted I give it an email address or it wouldn't play ball. I gave it my MS-account email (that happen to be an gmail account). I imagined Outlook would copy all the old calendar items. It didn't. New Outlook was blank.

I was going to start using Outlook before it forced me. Not because I wanted to but because it seemed, after searching for years, that is the only possible way to make a calendar backup.

I believe I clicked Add calendar --> edit my calendar (New Outlook) trying to find a way to make my calendar entries appear when suddenly all my calendar entries where gone. They never appeared in New Outlook and were gone from the tray icon clock as well.

I can add new entries to New Outlook and I noticed they appear in my gmail account (calendar) as well.

I've more or less given up retrieving my old calendar entries. Thankfully I don't really need them. Searching this community for tips I looked in New Outlook "Deleted items". It's empty.

Now the tray icon clock calendar isn't only empty, the "Save" and "More details" are both greyed out. Is there a way to restore the convenience of the old functionality. Meaning I can add items via the tray icon clock again? I also have a vague hope if this is restored all my old entries will reappear.